OK, it’s like this: Mizuno shoes are right on as far as size, meaning, a "12" is a "12." Simple. If you are at an 11.5, get a 12. If you are a 12, get a 12.5. The reason for this is that the shoes are built so well and they stay together under stress. Once your foot becomes "active" in the shoe from running around or regular activity, one may find that the shoe feels tight. Yes, feet expand like any muscle or group of muscles in your body when stressed. Again, the superior construction of the shoe keeps it true to its size. I have 3 pairs of the Speed Trainer 2, and also had the original Speed Trainers. I’m actually sitting here in my office on casual Friday with a pair on right now. These shoes are built to last; superior construction, with awesome arch support; plain and simple. I use them for running, cross training, and just as my regular casual shoe - the look is great as well; a fashionable shoe for anywhere.

It's a decent shoe - not great. I bought it because I needed new shoes for practice on indoor carpet (at the local indoor baseball facility) and bought them because the price was relatively low - on sale I think. Been out of work for a while. If I had an income, I would have spent more for a better shoe.