I agree with the others above... fit, finish, quality, etc. goes to the Tikka. Although I'm on a Salvage kick right now, I've owned five Tikkas and all have shot great.
I don't like the fact that the American doesn't lock the bolt. I can't stand that, but that may not bother you or your son.
Another thing I didn't like about the American was the mag release. It feels cheap and weak. I was looking at it at the store. With the mag out, I pushed the release and it didn't want to spring back. I reinserted the mag and it fell out. Maybe the release had already gotten broken, but it just seems flimsy.
Other than those two things, the American seems ok. Same with the Tikka-clone that Remington introduced.
