I pretty much concur with what my good friend, Ed, said above. And to add a bit more of what has been mentioned, a type from any of those sets listed is not too difficult. A particular player or variation can be super tough, if not impossible, though. And As someone who really enjoys trying to collect the rarest cards I think it's great, as how time has gone by, certain caramel issues are still rarely seen. Peter (hi Peter) didn't go into the really esoteric, mainly minor league issues, such as E221, E222 etc... but when I see one I always raise an eyebrow
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