I have 3 pair of the ON Clouds, 2 pair of Cloud Surfers and a pair of the Cloudcruisers. I trained and ran my first 1/2 marathon in the Surfers, it was a great experience. The cloud technology really helped me, I've had 2 knee surgeries and I didn't not feel the pressure in my knees. I ran a 4 person marathon relay since and I'm signed up to run a 1/2 marathon in March 2016, I plan to wear my Cloudcruisers. If you are looking for a great running shoe that's also stlylish ON Clouds is the way to GO!