I just picked up a pair of these for snowboarding. I haven't used them yet, but I've worn them around the house to see how comfortable they are for a few hours. So far they are great. I also got a pair of the CW-X insulator stabilyx tights because I have some minor knee problems. I thought these two products would be similar, but they aren't even close. The CW-X's are heavy, thick and spandex-like, like a heavy pair of bike shorts, while the X Bionic is much thinner . . . like a comfortable pair of lightweight socks.

I'm 5'6" and about 180lbs with 33" waist and big legs. According to the size charts, I'm between sizes for both garments, and got the larger size in both (L/XL in the X-B and M in the CW-X). Both of them ride pretty high on the waist, about halfway up to my chest. Probably partly because I'm on the shorter side, but I think this is somewhat intentional as well. It's good for snowboarding to keep the snow out of your back, so I don't mind. But because the CW-X are much thicker and heavier material, they tend to bunch up around my mid-section when I sit down and need to be adjusted all the time, whereas the X-B stay put and are comfortable in any position. The CW-X have much more compression than the X-B, possibly due to the sizes I got. The X-B doesn't really compress my legs at all. I don't think they will help my knee issues, but they fit snug and seems like they'll do a good job keeping my temperature regulated for most days on the mountain. I wear 2-layer Gore-Tex shell pants, and I think these should do pretty well underneath, but I might wear another pair of shorts to prevent my butt from getting cold while sitting in the snow on really cold days.

They also come in a pretty fancy box . . . I don't think I've ever seen nicer packaging for any product, ever. That could explain part of the high price.

I think its a great product, but I deducted one star because I was expecting more of a compression fit, because I wish they would come in a wider range of sizes, and because they are very expensive. I'll probably get the matching top at some point.