Not impressed with RC-M pinions

[RC-Monster Mike]

It is very rare to have a pinion wear out like you describe - in fact we have seen about 5 or 6 pinions with issues in the last couple years since we started selling them (so less than 10 bad gears in about 10000 sold) - as a rule, the gears are rock solid. Nothing is exempt from the occasional error, though - send your worn out gear back and we will replace it. Simple as that. I don't think you will find a better gear, though.