I also have some Altra shoes I really like - the most cushion I've ever had in a shoe and super comfortable to run in.

As Jope said - you'll want to have them try on some different shoes and see what your son likes. I really really wanted to like Nike, but the fit and comfort for them was always horrible on my feet, so I just couldn't do it.

Lately I've been reading a lot of articles suggesting that for training shoes you get something with a little more foam thickness to so some shock absorbing while putting on miles, then wear a lighter and springier shoe on race day.