I just bought a Diamond Outlaw and the manual that comes with it mentions upgrading the Razor Edge and Edge models to higher weight limbs for $84.99. I'm in the same boat. Going to get a bow for my just turned 7 year old next summer when he's nearly 8. For now, though, he loves shooting instictively with his Bear Scout which cost me $30 last year. I have a treestand set up 5 feet off the ground and he shoots down at my Glendel buck and loves it. The guys at the pro shop gave me the good advice of buying el cheapo right away if he never shot a bow before and give him a couple of years of trying that out before spending a couple of hundred bucks. No sense in buying what's not needed right now. That said, if he likes archery and wants to keep doing it, it's a great investment.