Re-using Used Lifters on Another Cam

I know of a couple people who mixed the lifters up on their solid cam and it ran fine.
Truth is the lifters aren't really flat on the bottom there's like a .002 dome on solids.

It's something I'm not looking to try, cuz if it fails... it's like dumping a couple paint caps full of iron dust after porting a head into your engine.

That's right. It's one of them "I ain't for sure if it'll work" things so why take the chance?