I was looking for regular black leggings fro everyday wear and dancing and these are very affordable and comfy. I looked at the measurements and went for a M because I am 5'9" and very thin. They fit like I expected, more of a capri because of the length of my legs, but that was how I wanted them. Suggestion, look at the inseam chart to determine how they will fit.
My daughter loves these to wear under tops - the new fad at her performing arts school. She's 5'9" and these are slightly short (in the med). We may try one in large. Got a tiny whole in the inside seam at first wearing and a whole in the rear by the end of week two. She didn't have a problem with them being see through, seemed to provide good coverage. She says they are fairly warm and very comfortable. She wants another pair - she can't wait for them to come in!!
I really love the fit of these leggings and they are super comforable. I am 5'7" wear a size 14 dress and the XL fit me perfectly. The rise is just right so that the waist band hits below the belly button and the cotton blend is nice and stretchy but firm. Only 2 things: I wish they were longer (my legs are average length but they didn't go all the way to my ankle) and they are slightly see through at the stretchiest points like the bum and the knee (you can actually see it if you hover on the knee of the website photo). So while I couldn't wear them with just a T shirt at the gym without the whole world seeing my thong, over a leotard or under a dress or something they are fantastic.