The crank in my Crossle 35 was in it when I bought the car about three years ago. I have no idea how long it has been in use or how many racing hours it has on it. The flywheel, to my knowledge, has never been in contact with curbs, etc., so I believe the crank hasn't seen that type of abuse. Both rods and mains are undersize.
My machine shop checked the crank for straightness and "wet magnafluxed" it. They found that it was true within .001" and had no evidence of cracks.
Should I have qualms about running this crank? Are there recommended guidelines for routinely replacing a crank with no apparent signs of distress?