little fyi..Aluminum pinions work fine, and for a long time..

IF, they're hard Ano (not sure you can get anything else now), you run a gear cover (who doesn't) AND you run indoors with relatively low dust. I tried one outside on an average dry, dusty track...It lasted 5 minutes, taking the spur gear with it. Not stripped but it was nothing I would use or keep running.

Actually I don't like any pinion that's not hardened, aluminum or steel. I'm sure the Losi's are and I run the RRP Absolute pinions. The $3 plain steel RRP ones (you can tell because they're shinny) are absolute (no pun intended) JUNK.