Re-using Used Lifters on Another Cam

Thanks guys. Honest replies IMHO. This was for flat tappet lifters (.842 Chevy size), no info on the engines, but probably stock stuff, with similar spring pressures as in SBM's .

The context was that a new guy to engines was considering putting some the used hydraulic lifters from his old head into a 40 year old head with a solid cam that had been setting for 30 years. I was saying no way you should do that and then foolishly said it would have a '99% chance' of failure.... trying to make sure this new guy got a sense of the risk. Then the person I quoted above claims to have done it successfully ' a dozen times' but with no description of the setups, and seems to equate new lifter failure as somehow as likely too.

I can't in good conscience let a new guys put his engine at risk. And I have asked how one would qualify a used lifter to be adequately good to re-use; not sure what to think of that matter.