Damn, you already took my favorite.
Is collecting the DVDs because they all had different commentaries/special features really that different than buying one (or several) reissues of the same album? Or special editions? I don't think so.
The VHS tapes were crap. They all warped. The first editions of the DVDs didn't come with the pilot. And the european pilot was extended and gave away the killer's identity! (sort of)
Hence buying all the versions...