Everyone has there opinon. Just like with every RC out there. Just like all the crap talked about The Xmaxx when first out. Take your time. Start slow see what works for your driven and what doesn't. It's all about trial-and-error bud....
Welcome to the RCT mad house of fun...
you will probably need more upgrades then just the diffs. To handle 4s. The whole drive Tran really. If it can't handle 3s. Your going to rip it apart on 4s for sure.