Great allround winter boot for a great price
I bought this boot for mixed winter climbing. I needed a boot mainly for winter mountaineering, but something that I can also use for moderate ice climbing and mixed alpine terrain. The mamook GTX is flexible enough to hike in, but thanks to its carbon sole, stiff enough for ice climbing and mixed winter alpine routes.

so far so good very pleased...
i love the light weight and flexibility in the ankle area... the sole is stiff which will be great for ice-climbing... will try an alpine route this july for overall mountaineering to see how well they perform... the size runs small so order at least 1/2 size larger... full size if you plan to use mountaineering socks or arch supports... as of now i would recommend these boots for climbing.

amazing - but with reservations
Light? lighter than my summer boots. Makes snow plodding much easier, agile and dexterous. Stiff? the stiffist sole I've tried even in size 10.5 just a trace of movement. Comfort (walking): fit is superb but not much tongue padding and right foot painful due to a hard edge cutting in - solved with a piece of extra foam. Sizing is very small - even 0.5 larger is too small to use the very fancy footbeds supplied. This means they are a bit cold; consider buying a full size larger than your usual UK size if warmth is more critical than climbing feel. Grip? the old style rubber is excellent on rock and has deep tread, not weight saving. But clogs in wet snow. Climbing? I've mainly used walking/easy stuff. They would be fine for the alps but maybe unnecessarily rigid soles on rock. The ankle mobility helps. Durability? no marks after 10 days. My real concern is these are a rigid sole on a very flexible upper - like strapping a piece of wood to your foot - when front pointing they give no help to keeping your feet flat - you have to use your muscles! Maybe great for the ultra fit on gynmastic ice, but very tiring.

Comfortable but UK sized
I had to send these back because they come in UK sizes, but they did seem pretty comfortable. I wasn't able to get replacements since Altrec was out of stock. The return process at Altrec is very slow.