C4.1 rear shock shafts

[neallewis]

I properly bent a rear shock shaft on my C4.1 on Sunday. I don't think I had an impact with anything, so it must have been from the bumps and jumps on the track. Mid-race, back end just seemed to stick as the wishbone was stuck half way in travel, and I retired from the race.
I'm running standard V2 AE shocks, as per B4.1 worlds kit. I didn't have a spare, but managed to get a spare from a fellow racer.
I'll be stocking up on these this week, but want to know is it a common breakage or failure? I'd not had one go on the B4.1, and I'd have thought the wishbone may have gone before the shock shaft. I guess it depends on the angle of impact? Anyone else?