Just received the tights. Now, I'm a skinny guy -- 5'11 140lbs with a 31" waist. Like the others have noted, the size medium is for someone with a waist smaller than mine. The leg length is perfect, though, about 31". There's no room for anything between the fabric and my skinny legs; these are tights! Currently exchanging it for a large.
As far as quality goes, it looks good. With a windproof front and breathable back, they're similar to the ones (not Gore) I'd worn out that these will replace. They have many separate panels that seem to allow for ease of movement despite its tighter fit. The 8.5" wide zippers at the cuffs have a 0.5" reflective strip their entire length. Finally, there's a tiny zippered rear pocket, good for a key, or a rolled up couple of bills, but not both!
I'm looking forward to using these for the rest of the cold mornings this Spring up here in New Hampshire.