These babies rock! Bindings can be adjusted with gloves and stay flexible in sub zero temps. Heel risers make hills cake, the frame has built in crampons. These things are lite and are very easy to trek with. Decent floatation. Crampons really work awesome whether uphill, traversing, or decending. Bush whacking is a blast with these things... feet stay well planted in the bindings... these are tanks. BOMBER STUFF! I got the 25 inch which handle up to 225lbs.
None.
I also looked at Tubbs Mountaineers. They have nice bindings but they're nylon.. which if wet could freeze and make adjusting harder. Also not the bomber crampon action that the MSR set has on them.