I never broke a Golden Rod - until I rattled the motor & broke other stuff first.
The RC guys had genuine surprise at hearing of a breakage - until I explained the circumstance. It was thier contention that those rods should outlast the bike.
I've used them in several motors and used to regularly twist the daylights out of them. I knew another local guy who had at least 10,000 miles on his Cobra motor with no issues, but he moved so I don't know the end life result.
I can tell you that I would have them checked for straitness and both ends for being round.
I have resized lots of BME's for the dragster (a no budget team but with a decent downhill slide on famous guy's parts) but haven't yet done my golden rods, drilling & tapping those bearing locator pins for jacking bolts might suck, then there's milling .002 off the cerations of both cap & rod. As long as the bolts thread in easily (BY HAND) to an assembled unit, the parting line hasn't been pounded apart by detonation and you are OK...