I run mine hot because engine is very strong.

what I meant to say was Engine "isn't" very strong.

"any good replacments??"
There are harden diffs and final gears available.

"and if there are, how much???"
I haven't bought mine yet so I dunno what the prices are. you can check towerhobbies.com

"what did it take to break them???"
hitting jumps and not letting off the throttle. when I run, its usually just WOT over anything and everything. I tumble and flip all the time. so I busted steering knuckles as well.

Wow Evo, thats a nice flippin ride. I want to do the rear exhaust too. what cheap pipes do you guys recommend?