I've had a pair of KSO's for about a year and really like them. Mostly I use them for running, which they work very well for. I would recommend finding a place locally to try them on, if at all possible. The ideal fit is pretty snug, like gloves for your feet. Also, I'd recommend taking it slow when you first get them unless you have completely ridiculous leg muscles. First week, I wore them almost exclusively for walking and light jogging only a few hours per day. Second week I moved on to jogging and light running. By the third week I was good. Not only do your muscles have to adjust, but it's easy to forget to not heel strike when you first get the shoes. If you're not careful, you can end up with some nasty heel bruises.