The Mountain Trainer GTX is a low cut alpine approach shoe which features, amongst other things a midfoot via ferrata zone, three-zone lace tensioning and Salewas '3F' system which connects the instep area with the sole and heel.
The lacing system is a triumph of design and one of the best we've seen. It extends right down to the toes and features locking eyelets, so you can tweak the laces to each area of the foot individually. The locking eyelets are set just above the forefoot, with another controlling the mid-section. The bottom set allows you to fine tune the toe area depending on usage and physiology. I was able to get a precise forefoot fit which still let my toes splay naturally. The top set of eyelets set the fit from the instep to the heel. This is where the ingenious 3F system comes into play, it consists of a thin metal cable that runs through a rubberised locater from the top eyelet down to the instep and around the back of the foot. I tend to suffer from heel lift but I'm able to dial that out in the Mountain Trainers without affecting fit across the rest of the shoe. You could achieve a similar end result using different lacing methods, but this is a much easier and more effective system.
In terms of comfort the ankle and tongue are generously cushioned which successfully protects against potential abrasion from the lacing system. The heel feels well cushioned with good shock absorption and rebound, there's a bit of trail feel through the forefoot but not so much that it becomes an issue.
Stability wise, aside from the excellent lacing, the 360-degree rubber rand not only protects your foot from damage, but it also does a great job of stabilising the upper. The sole is mid stiff, with just a touch of flex in the forefoot and very little flex laterally. This inspires confidence across challenging terrain where my feet felt planted at all times, and I felt there was very little risk of a rolled ankle.
Grip in the Mountain Trainers is phenomenal thanks to aggressive, deep lugs. These shoes climb and descend tricky terrain with ease, inspiring absolute confidence. The pronounced heel brake gives way to an instep which houses two via ferrata lugs to give you an advantage on iron ladders. These don't get in the way of usual hiking duties so don't let them put you off if via ferrata is not your thing.
There's a bit of roll off the heel on to the forefoot and the sole has good rebound, these two factors help reduce fatigue in what is a fairly heavy shoe, at 540g. Having said that, it's a fair weight for the high levels of stability, protection and traction, not to mention comfort.
Seriously high-quality construction and well thought out design, leading to serious mountain applications usually doesn't come cheap and the Mountain Trainer is no exception at £160. Whether its worth it is down to the individual but based on the merits of the shoe itself we say it is.