I've owned a pair of 44.5 for about 6 months now. That's a size or two bigger than I would normally wear. I've worn them a few times at 10-12,000 ft in AZ in January and on Mt Rainier in early June. I've warn them with the original footbed and the thin Superfeet footbed. Sometimes I wear the tongue insert to give a snugger fit, but I've also worn them without to give more space, thinking that my feet were cold due to constriction. I've tried various sock combinations, but typically wear a vapor barrier with liner sock and thick wool sock. In AZ I've gotten mildly chilly toes while standing around, but nothing serious. On Rainier, I lost feeling in my toes and had trouble wiggling them due to the cold. I may have expected too much with these boots, but I don't think they're all that warm in the toes. The rest of my foot has always been fine. I personally wouldn't take them out for significant "winter mountaineering" as shown to the right on this page as a "Recommended Use". If you check the insulation in the toes it's very thin. I'll probably try another footbed to see if I can stem heat loss through the sole, but my toes have also felt cold across of the top when it's been an issue. The boot definitely doesn't seem too tight either.
I'll probably keep these for doing 14ers in CO later into spring, but I'll also probably be picking up a pair of Baruntse so I don't have to worry about it anymore on multi-day trips.
All in all, I think the boot is well made, but probably not warm enough for me for some of the things I like to do. I've never considered myself prone to cold feet before, but it is possible that my circulation or other physical issue is causing the problem. I don't think it should be advertised as a "winter mountaineering" boot. It's ok for quicker day trips, but for multi-day trips something warmer might be necessary or recommended IMO. For extended cold weather trips I'll definitely be picking up a pair of double boots.