I'm with you on the diffs...not sure why they are so rough compared to the other cars out on the market??? Even after I clean and lube thoroughly in a rebuild, they are really grainy feeling after a few runs...Speaking of diffs, I've been having problems with the plastic outer shields on the rear diff coming off partially...I may just need to replace them, but they wont stay snapped on...
Other than that, once the parts get here later this week I'm going to do the roll center mod on my car, then reset it for asphalt parking lot racing again...we lost our indoor carpet track..