Thinking about getting my son a new bike for Xmas, and looking for suggestions. He's 5'2" and a fuzz over 100lbs, but likely to grow fast (I'm 6'4"). He's not a very aggressive rider at this point but he spends a lot of time skating the local parks so he will probably end up riding his bike in the parks sooner or later too. I want to get him something that will work for that and maybe some dirt jumping/ trail riding.
I can spend around 400$. I'm guessing something with a 20.5 TT would be best so he doesn't outgrow it too soon but I would appreciate any input on size and brand in general, and any specific models that are good deals.