I'm a longtime Asics fan and have worn several styles over the years - always a size 12 - but they had a narrower toe box than usual and were pinching my toes (would definitely cause an ingrown toenail cause on my big toe when I wore them) - so had to be sent back (unfortunately at the expense of return shipping). Bottom line: Still like Asics, but I'll just be buying brick and mortar - so I can try it on to ensure proper fit/sizing accuracy - from now on. It would be nice if Revain Prime customers offered free return shipping if they got the wrong size.