I had ACL reconstructive surgery in March of 2013 due to a skiing accident and was pumped to get back on the hill this '13/'14 season. I made the decision to get a knee brace to protect my new ACL and had the hardest time finding tights that would fit with the brace. I love merino, but due to the wool fibers and overall texture the brace fit horribly and also irritated my skin. I had heard good things about CWX so decided to try out these tights. THEY ARE A GAME CHANGER. Not only does my brace stay on 100%, these things are as supportive as everyone says. They increase circulation, are breathable, are damn comfortable and do not irritate my skin. If you are in unsure of sizing, I recommend going by height. The way the supportive webbing is structured means that you will get the most benefit by going by your leg length. I am 5'2" and went with the small. Be warned, these will be tight like a tiger, but thats what you want in compression tights!