regarding sizing, I bought a pair of size 8 Abyss boots, after talking with a guy at OTB about the sizing.

I wear sz 8 shoes, but 8 1/2 in hiking boots to have extra room for thick socks - I normally wear 3 layers; a thin liner/wicking sock, a lightweight wool sock, and a heavy weight wool hiking sock.

In the Abyss boots in sz 8, with the first two liners (I've never added the 3rd/extra liner) and my 3 layers of socks, I get a perfect fit.

So I'd say if in doubt, either call OTB, or go with the lower size - could be the other models are sized differently I guess, so calling them wouldn't hurt.


EDIT _ they have a sizing guide on thier website -- for water boots, they say if you are wear a half size, and that half size is on the big side for you, then buy the OTB boot in the smaller size;  if your half size boots are snug, than buy the OTB boot in the next larger size.