These are nice quality, thick, and soft. According to the size chart and other reviews, I ordered the L/XL. The size is comfortable in the legs, but the waistband goes all the way up to my bra and is a little loose so it doesnt stay put. They also sag in the crotch area which is annoying when walking. To be fair, I don't wear them for dance (as a leo would probably help with this problem). I am a server and ordered these since they are more durable than typical nylons. For reference, I am 57 and 120 pounds. The S/M probably would fit better.