The ONLY real problem I've had is the throttle servos. I fixed the brake cam binding with the twist of two screws. I've heard of the shock issue, but that can be fixed very easily, by simply giving the locktite time to dry. AFAIK, these are the only common issues, and in time, we'll get the thottle servo issue figured out.
This car is awsome, and though my experience with it is a mere month, I can tell you it's been through the ringer, and come out on top. It's durable, fast, and serves its intended purpose, racing, very well.