For a leather B2 boot the Kento Advanced High are very light, says Toby Archer, while being comfy to walk in and performing well for climbing and scrambling in any season. For something this versatile the price seems more than fair, too.

The Kento Advanced High GTX are light, supportive, comfortable and watertight. They are also competitively priced compared to similar styles of boot from the big name Italian brands. This is a B2-rated mountaineering boot, compatible with semi-automatic crampons. OK, it wouldn't be the first choice for climbing that involves sustained front-pointing (be that on ice or technical steep mixed) or for use in deep winter cold, but beyond that I reckon there aren't many UK or summer alpine trips that this boot couldn't be used for. Thanks to their low weight and nimble feel, this is one pair of B2s that I've actually been happy to wear in spring and summer.

Having received the test boots in mid-April I've not yet had a chance to use them in winter conditions. I have, though, done a lot of scrambling and easy climbing in the Kento Advanced, so I have a decent idea of the support they give when the toe is on small holds - and that is plenty. Thanks to their lightness I will happily use them for fast-moving days of winter scrambles and ridge traverses in the snow this coming winter - routes like Crib Lem, Striding Edge or the Fiacaill Ridge - although it is worth noting that in a size 8, mine will probably be stiffer and feel more secure with crampons than if you have size 12 feet [tell me about it - Ed].

For leather B2 boots they feel wonderfully light

For all UK mountain use short of pitched winter climbing I would say the Kento Advanced High are well worthy of consideration, be that winter walking, easy mountaineering, summer scrambling or even backpacking.

But there is one potential caveat over their durability: on my test pair the sole is starting to peel away from the toe of the boot. This is small, literally a couple of millimetres, but easily noticeable. I first spotted it a couple of hill-days back, and delayed writing this review until I could use the boots more and see if it got worse. I don't think it has, and indeed it could have happened when I first used the boots and I just didn't notice it under mud and dirt.

The sole unit must come under extreme stress at the very front, and I've had many pairs of both mountaineering boots and rock shoes where the sole has "peeled" very slightly at the toe. This is always disappointing but I don't think I've ever returned a pair of boots because of it. As I use the Kentos more this autumn I will keep a close eye on this spot and update the review if the peeling gets any worse.

Weight

Mammut's website gives the weight as 645g per boot in size 8.5/43. One of my size 8/42 boots weighs 594g (1175g for the pair, and yes - if you are quick at maths, that does look weird. Getting to the bottom of this, I found one of the boots is about 10g lighter than the other: They are handmade items I guess).

They feel wonderfully light on my feet, closer to approach shoes than traditional leather walking boots. From past reviews I have a couple of pairs of other light, crampon-compatible boots, both of which take semi-automatic crampons, although interestingly I believe both were given a B1 rating, unlike the Mammut's B2. Although those older boots have always felt very light on my feet, the Kentos are lighter than both, and a major attraction is that they must be among the lightest B2-rated boots available.

In use 

Here I can sing the praises of the Kento Advanced High with the only proviso being my concern over the sole. While they feel really light, at the same time they are stiff and very supportive. Mammut have hit a sweet spot between good support for walking over rocky and uneven ground and when actually climbing in the boots - edging or "toe-ing in" to small holds - and on the other hand being flexible enough that I can happily hike over non technical terrain without getting sore feet, where normally a soft hiking boot or trail runner would suffice.

OK, I wouldn't choose the Kentos for a long distance hike like the Pennine Way, but I have worn them very happily for weekend backpacking trips in the Lakes and Peak where doing some scrambles was part of the plan.

The Vibram sole grips well on dry rock, and as well as any sole on wet and greasy rock - don't expect miracles, but they are up to Vibram's normal high standard. The tread is aggressive enough for damp, grassy and muddy British hillsides.

Fit

The Kento Advanced High GTX is available in both a men's and women's (lower volume) version. The size range is from UK 6.5 to 13 in mens and 3.5 to 8.5 in women's - a good range.

Drawing objective conclusions on fit from subjective experience is always hard, and as ever the best advice is to try them on for yourself. I would suggest the fit is on the small side. I have worn size 42 mountain boots (normally UK size 8) since my first pair at the start of the 1990s. In some wider fitting models 42 can be slightly loose on me. I have wide feet so have traditionally needed 42 to get the width, even if that leaves lots of wiggle-room for the toes (not actually a bad thing for winter climbing). But as a result I have found with a few brands that UK 7.5 (sometimes given as 41.5 but also as 41) is a better fit, particularly for boots aimed at climbing and scrambling - it sounds a bit ridiculous for a punter like me to call it a "performance fit" but you know what I mean I'm sure.

With the Kentos I ordered the 8/42 size and wondered if my feet would be too loose in them, but when they were delivered it was the opposite. I even considered swapping them for 8.5s but am glad that I didn't. I've worn them all summer with thin, well fitting socks and have not had any problems - not a blister, hot spot or rubbing point even when they were brand new.

Indeed the only slightly odd comfort issue I have found is that if I tighten up the left boot one of the upper lace hooks pushes uncomfortably against my ankle, but only on one boot! There's a locking point halfway up the lacing. This means you can have the laces loose over your foot but tight around the ankle or vice versa. I've found with the laces snugly holding my foot in place then locked, I can leave my left ankle relatively loosely laced and this avoids the pressure point from the lace hook. After working this out, I'd say they are one of the most comfy crampon-compatible boots I've used.

Design

The men's boot is available in three different colour schemes (two in the women's). I rather like my red ones, but the blue ones are also funky.

It's interesting to see leather used in such a light boot, as opposed to synthetics. As usual, this is backed up with a waterproof membrane. Ultimately all Gore-Tex linings in footwear eventually seem to fail. In older boots I own, this happened in less than a year - probably only a week or two of use on the hills - in the worst case, while other boots have remained waterproof for many years and dozens of days of hard use. I do find that with more rigid B3 boots the liners seem to last longer than in softer models. This makes sense as presumably flex and wear ultimately breaks the liner at flex points. The Kentos are surprisingly stiff underfoot for such a light boot but they do flex (and are comfy for hiking in as a result) so eventually I suspect they will leak in wet conditions. But so far they have been completely watertight and I happily walk straight through streams in them. I suspect the high rubber rand and then nubuck leather that makes up the outer will do a lot to stop water even getting to the Gore-Tex, but the sewn in tongue is made of a soft nylon material and extends to the toe, so this is one spot where the boots are reliant on the liner to be waterproof.

The final comment on the Kento Advanced High has to be on durability. I have described my biggest concern above: the very slight peeling of the sole away from the toe of the boot. If it was to get suddenly and significantly worse, a paying customer should expect the manufacturer to replace the boots without complaint. If it doesn't get any worse I will probably not worry about it. In some ways the middle ground is hard: if you look at your boots after each use thinking "has a millimetre more sole peeled away?" and "is the sole of my boot going to fall off when I'm halfway along the Aonach Eagach?" It is a real shame because otherwise the durability seems excellent. Considering most of the days that I have worn them have included tough rocky hiking and scrambling, the uppers remain in perfect condition beyond some dirt and scuffs.

Summary

Overall there are loads of positives about the Mammut Kento Advanced High GTX that make me want to recommend them for the UK mountains or alpine climbing for any setting - summer or winter - not involving extended crampon use. They are very light for a boot that can take semi-step-in crampons; they're comfy on long walking days, yet they also climb and scramble well. The price seems very fair too. Just keep an eye on the sole at the toe. I will report back if my review pair get any worse.