I've worn Asic shoes before and found them to fit true to size, but this felt a little too tight for comfort, bordering on painful. I do have somewhat high volume feet, but not so much that I needed an extra wide shoe. However, as of late I've tried several running shoes with Gore-tex and tightness around my foot has been common with each of them. I'm not sure if the fact that they have Gore-tex is a contributing factor, or if I just happen to be choosing shoes that are too narrow for me. Regardless, if you're like me and have a slightly fat foot, I'd suggest going up half a size.