The AKU SL Pro GTX is rated as B2/B3, so it is stiffer than a normal B2-rated 4-season boot and so when compared with other B2-rated 4-season boots it is just too stiff. For hillwalking this is a drawback, as it is quite uncomfortable underfoot. However if you were looking for a boot for mountaineering and climbing rather than purely yomping over the British mountains in winter, then this is a real contender as it does compare well with other climbing-orientated boots that are rated as B3. It is built around a synthetic upper with a rubber rand for extra protection. The outsole is a Vibram Mulaz unit, which is well-proven for climbing and mountaineering. It has a slightly shallower pattern of widely spaced lugs than walking or more general use B2-rated 4-season boots. There is a smooth climbing zone at the toe as well. On the foot this gives a very precise feel under the forefoot area, making climbing in these with or without crampons a really precise and safe occupation. But on the walk-in or just when tramping across winter hills that stiffness and lack of cushioning in the forefoot is not as comfortable as a B2-rated 4-season boot. But if you are spending all day mountaineering and climbing then the AKU SL Pro GTX is a great option.
Upper materials Air8000, Thermoplastic PU
Waterproof lining Gore-Tex
Sole unit Vibram Mulaz
Women’s sizes none
Men’s sizes 7-12
Weight 2082g (pair, size 11)
The AKU SL Pro GTX is a superb climbing and mountaineering boot, but by definition is it not as comfortable as others if you are going to spending most of your day walking.
Review by Graham Thompson
Just missed out on being in Trail magazine January 2014