I bought the SDJ Orange and Purple ($13 each, guy wants $499 for the Super? The actual Super is probably barely worth that)
Anyway, they are noticeably larger than the real thing, but the quality is surprisingly high. I only got them as a unique, fake, gimmicky piece to my collection but outside of the fact that they aren't serial numbered they are very convincing.
I don't think it would be too hard to replicate the 1/1 or any number Topps adds.
Seems pretty suspect, and I am already worried about people counterfeiting BGS cases (also would not be too hard for a motivated individual)
I collect Royals cards serial #'d/99 or less from Bowman
Here is my collection: http://tinyurl.com/TBCG-G