I normally wear a 10-10.5, but bought an 11/12 based on recommendations.  It is too large overall, which makes it have too much room inside, and the heel slips.  It also doesn't look as nice as I had thought it would - not bad, but too close to its Australian cousins, i.e., kind of boat-like, with colors that are a little duller than expected.  The genuine sheepskin, however, is nice, and it looks like it would be a warm, comfortable boot, but due to sizing, I have to return it.