Lowered my 3 mile run by 1:30 ... crazy! So light, and yet such comfort when striking pavement.. This is not a trail runner, so if you plan to run on trails, rocks, sand..this is not the shoe for you, but if you're running on a track, pavement, asphalt, etc...these are love! Will be buying these from now on. I try to buy a new pair of running shoes every 6 months or 500 miles.