If I'd been able to try them on I wouldn't have bought them. Based on reviews I ordered size 11, 1/2 size larger than my normal shoe size which appears to be correct. That is my toes are where they should be and the heel is where it should be. However the fit is very loose and my heel moves vertically in the heel cup. The heel movement is guaranteed to cause blisters. Perhaps I could improve the excessive interior volume using insoles and tight lacing, although a boot that starts loose will only get looser, but there's another deal breaker.
As pointed out by another reviewer for whom English is probably a second language, in the center back of the heel cup is a glued overlapping leather seam which forms a sharp edge. Coupled with heel movement that's guaranteed blisters. Were I to keep these I would immediately fit a generous piece of Moleskin over this seam and hope it stays put.
I wanted to like these boots. They're super light, appear well built (apart from the heel seam), appear well ventilated with a moderate tread. They also use 4 Nato Eyelets (6 would be better) for lacing. If you haven't used Nato Eyelets they're great. One pull on my Timberland's (sadly no longer in production)  laces 5 eyelets from calf to instep. Unlace with similar ease. I'll look for them on any boot I buy.
The bottom line for me is they just don't fit properly. Perhaps you'll have better luck.