In reply to doz:
I bought a pair of these this year as the last time I was in The Alps my feet were too cold. My feet were toasty this year, though it I have to say that, subjectively, it didn't feel as cold this year anyway. I reckon they probably are pretty warm though - bordering on 'too warm' in the valleys in fact.
So I suffered a little bit at low altitude and had a couple of blisters early on. This did seem to sort itself out after a few days. Once hight up I really liked them. They felt good on rock or snow (Grivel G12 crampons).
I did replace the footbeds with supafeet, but I'd always do that anyway.