Hey bro I picked up a B4.1 RTR and it's becoming my favorite vehicle, especially for the track. You can get away with the stock motor/esc for a while. I changed the servo to a futaba 3305 and it works perfectly, you don't need a monstrous torquey servo since their so light, the 3305 works well and 35$ bucks new. I would also reccomend factory team arms in the beginning and eventually v2 shocks and ball diff. It's a capable chassis just takes a lot of tweaking