I've broken a rear shock tower and rear upper arm mount (replaced with Tamiya option part with 2 braces in it). Apparently, Kyosho RB5 or ZX5 ball cups work well with the Tamiya ball studs. I have some coming and hope to try them soon. I am truly shocked though that more cups have not come off in racing since one can remove them without pliers!
I have a big race coming up and I will have to grab a spare front shock tower (probably the Tech Racing thicker model from Jason's Store on eBay). Great vendor BTW!
veecee, thanks for the tips on the aluminum castor block! I do race indoor off-road on a sticky surface and sounds like using the inner most ball stud positions is ideal?