I wear a 7 1/2 or 8 and bought these in 8M, antique soft full grain, black.  This size is perfect for me.  I had to put a liner in the foot bed because it was a little stiff on the first day.  Be careful, the soles are slick and need to be scuffed to prevent slipping.  I'm 5'2" and the height on these is perfect, about an inch below the knee.  I've been wearing over skinny jeans.  A little difficult starting the zipper but not too much.  Unlike other reviewers, I have had no trouble with the snaps coming undone.  The boots were a little tight on the top side of my foot below the ankle but that has eased up as they've stretched a little there and now they are fine.  I will probably order a second pair.  No seam up the front of the shaft, which I like.
UPDATE:  I purchased a second pair in faun.  I like them and the fit is really good, a bit taller shaft, but they don't look quite as fitted as the black ones around the ankle.  The color looks good with black, grays, navy, and red, some browns, and loden, but I would only recommend this color if you already have boots in the more traditional browns.  I had to return the first pair of faun boots because there was a manufacturing flaw in the zipper, but the return process was fairly easy.