Love mine. Started with KSO Trek model. You can't tell it by looking at it now, but when I was born I had a clubbed foot. Whenever I'd run or work out, it would ache a little and fall asleep with running/athletic shoes. My other leg would start doing the same because I was favoring the other. It was a vicious circle and I just lived with it. I found if I ran barefoot, I didn't have the problem, but it was hard to find a place to run that was clean without rocks, glass, etc. About the only time I could do that was on a treadmill, which I hate. The FiveFingers have been a Godsend and I've not had the problem since wearing them.
I've since bought a pair of the regular KSO's for working out because the Trek tread was too grabby for some of the jump training, etc. in the P90x training I've been doing. I feel as though they are strengthening my ankles and the muscles in my feet and calves.
The Trek's have since become my everyday shoe. I just can't describe how good they feel. They are great for light hiking, shopping, whatever. They are FANTASTIC for travel. They do look goofy (my kids call them my Gorilla shoes), and you get some stares, and some bolder people will ask questions or simply point and laugh. I have the last laugh though.:thumbup:
Another benefit is that they are light for travel and packing (heck you can put them in your back pocket like a pair of gloves if needed), plus you can just through them in the washer if they get really dirty.
There were some comments in this thread too:
http://www.bladeforums.com/forums/showthread.php?t=730361