I put on a brand new pair, size 12 and walked probably 10 miles in varied terrain in 80-85 degree weather carrying approx 40 lbs on my back.
Not a good idea in brand new footwear, usually.
these speed freak boots didn't create a single hot spot, no blisters and my feet were cozy all day long - if not a tad hot but heck it was a warm day and I had on some pretty spendy socks to help too.

I can reccomend these
my only gripe was the toe when bent as you step forward had a tendency to flop back flat and make a funny clop noise. Shoes were a half size too big though, I would have gotten 11.5 but all the had was 12 and I figured I'd wear thicker socks in cooler weather.
On the UA site there are some complaints they aren't staying dry, like the gortex is flawed.
I hope mine stay dry! Seems like the guys in dry climbs are happy, and the ones in the wet stuff aren't.