Salomon X Ultra 4 GTX review

We believe that it's worth investing in the Salomon X Ultra 4 GTX if:

• you need a shoe for backpacking trips with a heavier pack but don't want a high-top boot
• Add a shoe
• Adidas Terrex Swift R3 GTX
• Toebox width - big toe old method

The Spire GTX's high price point can be a deal breaker for many people. But luckily, there are a few solid alternatives with similar features but more moderate price tags.

The Our caliper measured only 103.9 mm in the widest part of the shoes midsole in the forefoot is equally stable but is also notably lighter, more nimble, and flexible. Another excellent option is the Adidas Terrex Swift R3 GTX.

Ladies and gentlemen, we have a height champion in our lab! The Spire GTX towers over all the other hiking shoes at a whopping 39.1 mm!

Having this much platform translates to unparalleled foot protection from the trail obstacles and amazing support for the longest backpacking hauls. We felt 100% isolated from the trail as this La Sportiva shoe gobbled roots and rocks like chicken nuggets.

On the downside, this tall shoe will not be your best friend on rocky descents or any other shaky surfaces as it feels a bit tippy.

The shoe's platform gets notably thinner in the forefoot but it still packs plenty of foam to keep the balls of feet well cushioned.

A forefoot stack of 23.1 mm is slightly taller than average too.

A forefoot stack of 23.1 mm is slightly taller than average too!

Even if you never pay attention to drop in hiking shoes, you are very likely to feel your heels elevated in the Spire GTX.

Toebox width - widest part old method backpacking shoe. This setup puts your feet in a more ergonomic position to carry heavier loads on longer distances. It prevents your Achilles and calves from working overtime.

Despite its use of Compression Molded EVA, there is hardly any compression in the Salomon X Ultra 4 GTX. It is a stout shoe that's meant to be stable above all else.

Measuring its midsole softness with a Shore A durometer, we got a higher-than-average reading of 32.6 HA. That is 20% firmer than a typical hiking shoe midsole.

But even though plushness and Spire exist in parallel universes, we found that the shoe took very good care of our feet on long hikes. We never felt as beat up after wearing this La Sportiva shoe as we did after more grounded options.

If you are planning a multi-day hike where temperatures drop very low at night, it is good to know that the Spire GTX gets even firmer in cold conditions.

We kept the shoe in the freezer for 20 minutes and then repeated the durometer measurement. The reading went from 32.6 HA at room temperature to 38.0 HA after the freezer test. With a 16.5% change in firmness, this La Sportiva shoe is going to need some breaking in first thing in the morning.

As a cherry on top, the Spire GTX uses an OrthoLite insole for a more pleasant foot-to-boot contact.

Even though it is slightly thinner than average at 4.2 mm, its ergonomic contours still make it feel nice and cozy.

And a nice bonus: this Ortholite Hybrid is made with 5% recycled rubber and 15% production waste foam.

We found the toebox fit of the Spire GTX to be on point in our regular D medium width and the gel mold of the shoe's interiors confirmed it.

The distance between the shoe's most extended points in the forefoot returned a standard reading of 94.02 mm.

The shoe's toebox also has a fairly rounded shape which is reflected in a caliper reading of 72.72 mm at the big-toe mark. The taper angle is very mild in this La Sportiva shoe.

The vertical toebox space did not disappoint either. WIth a caliper measurement of 26.3 mm, it is on par with the average of hiking shoes.

If you are looking for boot-level stability in a low-cut shoe, the Salomon X Ultra 4 GTX is built just like that. From the bottom up, its construction kept us steady and surefooted as we hauled a heavy pack across challenging terrain.

Toebox width - widest part new method.

Its tall and sturdy sidewalls wrap around the foot on both sides creating a secure cradle and preventing any unfortunate buckling.

Carrying up to 20% of your body weight on the back, the last thing you want to experience is foot wobbling. That's why unyielding shoes like the Salomon X Ultra 4 GTX exist.

Our attempts at twisting this hiking shoe in our manual test had very little success. Thus, we rated its torsional rigidity with an above-average score of 4 out of 5.

Even if you have conditions like flat feet followed by overpronation (excessive inward foot rolling), you are going to feel very stable and supported in the Spire.

The shoe's highly rigid heel counter also takes care of any unwanted play in the rearfoot.

Giving the back of the shoe a good push and squeeze, we felt so much resistance that we never hesitated to rate the shoe's heel counter stiffness with the maximum score - 5 out of 5!

Interestingly enough, the Salomon X Ultra 4 GTX feels exceptionally stable even without a very wide sole.

Our caliper measured only 103.9 mm in the widest part of the shoe's midsole in the forefoot.

Adidas Terrex Swift R3 GTX.

If you are coming from a chunky platform (like those of Hoka and KEEN), we should warn you that the Salomon X Ultra 4 GTX is going to feel different. In our wear test, we felt as if the shoe's smaller landing area forced us to be more conscious of our foot placement in the first few miles. But after a short adjustment period, we didn't experience any issues.

With its reinforced construction and sturdy STB control system, we were not surprised that the Salomon X Ultra 4 GTX is one of the stiffest hiking shoes we've tested.

It took about 30% more force to bend the Spire to a 90-degree angle compared to an average hiking shoe. But as a result, you get the benefit of a more stable platform with more predictable steps.

We were glad to discover that the Spire GTX doesn't get significantly stiffer in low temperatures. After 20 minutes of cold exposure, the shoe needed only 5.5% more force to bend.

Considering the shoe's beefy design, we are surprised that it's not among the heaviest hiking shoes on our roster.

Showing 14.8 oz (420g) in a men's US size 9, the Salomon X Ultra 4 GTX is only 1.5 ounces heavier than average. The shoe never weighed our feet down as much as we thought it would.

Testing the Salomon X Ultra 4 GTX, we were particularly curious about its unique ePE Gore-Tex Surround waterproofing. Unlike the conventional GTX, this technology encourages ventilation not only in the upper but also in the sole! A 360-degree ventilation of sorts.

Of course, we are not talking about full-fledged breathability here because it is a waterproof shoe after all. As you can see from our breathability test below, none of the smoke we pumped into the shoe was able to escape through the fabric.

And yet, the GTX Surround helped our feet feel a little less suffocated in the Spire GTX because it managed to expel some of the built-up heat from the shoe.

On top of the shoe, the synthetic Nano Cells 2.0 material is responsible for maintaining a balance between waterproofing and breathability.

Synthetic overlays dominate the upper protecting it from water and debris while the mesh inserts provide some essential aeration.

Even though the Spire GTX has slightly more airflow than shoes with standard Gore-Tex, we didn't find the difference sufficient enough to increase the overall breathability score to 2. It is still a warm and watertight shoe with the lowest breathability score - 1 out of 5.

The Salomon X Ultra 4 GTX is one of the sturdiest hiking shoes we've tested. But even though its high-wear areas are very thoughtfully reinforced, there are a few weak parts to be aware of.

For example, the Nano Cell areas that are not covered with thick protective overlays (like the top of the toebox). Exposing it to sandpaper for 12 seconds, our Dremel left some notable scuffing which affected the shoe's waterproofing features.

Midsole softness in cold.

The mudguard, on the other hand, has fantastic abrasion resistance. You can be confident that bumping into roots and rocks is nothing more than a light tickle for this burly piece.

To our disappointment, the mesh lining on the inner side of the shoe's collar failed to resist the Dremel as well.

Considering all the in-shoe friction this area experiences, we expected a more hard-wearing material, especially after seeing how well the same part did in other hiking shoes.

Thus, we rated the Spire's heel padding durability with a low score of 2 out of 5. 

On the bright side, the outsole of this La Sportiva shoe proved to be indestructible. Our durability tests below prove that its Vibram rubber is pretty hard and abrasion-resistant.

Pressing our Shore C durometer against the outsole returned an above-average reading of 86.1 HC. As a firm rubber compound, it is capable of taking more abuse before it starts to show significant signs of wear as opposed to softer rubber.

You can see how stoically the Spire's outsole resisted the sandpaper tip of our Dremel in the test below.

Even after 22 seconds of drilling it at 10K RPM speed, the rubber sustained as little as 0.8 mm of damage. Tread loss is not even the right word here, more like brushing the dust off the surface.

The outsole thickness is also pretty solid showing 2.0 mm on our caliper. Paired with 4.3 mm deep lugs, it promises a long lifespan for a hiking shoe.

Featuring a pretty toothy and aggressively-looking tread, the grip of the Spire GTX didn't falter us once. The shoe kept a hard bite as we were navigating rocks and creeks, forging through some loose terrain, and wading the river banks.

Our caliper measured the shoe's lug depth at 4.3 mm which feels equally at home on hard-packed trails, rocks, and muddy stretches. This is thanks to the slanted and opposing angles of the treads of the Vibram XS Trek outsole.

The shoe's Impact Brake System inspired confidence on steep descents as well. It is much more pronounced compared to other hiking shoes.

The asking price of the Salomon X Ultra 4 GTX is pretty steep for a hiking shoe but it is right on par with the average of hiking boots! Even though we can't completely agree with the shoe's full price, there are a few characteristics that make the Spire worth the extra cost in our opinion:

• exceptional stability makes it feel a lot like a backpacking boot but without the high collar
• unique Gore-Tex Surround waterproofing with ventilation ports

But if that's not what you value in a hiking shoe, it's hard to justify the above-average price point of this La Sportiva offering.

There are no reflective elements on the Salomon X Ultra 4 GTX but the silvery membrane that peeks through its midsole ports gleams slightly when hit with light.

The Spire GTX offers a very welcome and cozy step-in feel. We found the shoe's internal padding pretty abundant without being too much.

Measuring its tongue thickness returned 9.3 mm on our caliper and there is just about the same amount of foam packed inside the shoe's collar.

This La Sportiva shoe offers a very secure hold around the midfoot too thanks to the full-length gussets on both sides of the tongue.

Another benefit of this design is that you don't have to worry about water seeping into the shoe through the gaps.

A finger loop is added at the back of the shoe for an easier on-and-off action.

If you are not happy with the Spire's stock insole, it can be easily removed and replaced with an insole or a custom orthotic of your choice.