There are still some V2 versions with the delrin poppet out there. That's not abnormal. V2's were out well before the metal poppets were.
You should see a difference in reliability for one thing. Perhaps a bit more consistent as well. Since their rebuildable, it should be the last one you ever buy as well.
Etek 3LT grey/black f/s
Valken Proton greyish/black f/s
68 4500 PE stubby, LP output f/s
68 4500 AIR tank(no reg) f/s
Creed Battery, eyes and noid f/s