I've enjoyed Cuddl Duds for years. The inside is brushed for comfort and the outside is slippery for ease of layering. I ordered large even tho I'm average size because they seem to run a little narrow in the hips. The large is perfect. Well, a little long, but I can hem them to the desired length. I already had white, but sometimes they show at the bottom of my dark colored pants. The black won't be obvious with my navy, dark green, dark brown or black even if they do show a little.