i wouldn't get a mick thonpson or noodles model because they're both korean made. that easy :P
but, to answer in general as your question was intended:
is appealing for the discontinued radius shape , it's somewhat special. others... modded stock models, more or less cosmetically.
i personally don't like signatures.
i like signatures that have something special on them playability wise;
for example: The JS
Radius body (radius is not available anymore)
the special designed MM Petrucci
unique pickup config + shape of the MM Morse
i dont like the punkrock guitars, they're mostly stock models stripped to one humbucker...
i dont like RG signatures, becase they're all pretty much RG's with custom cosmetics.
PLEASE don't flame me for this, but i'd never buy a new JEM7VWH if i can get a new J custom which has the same inlay and in my opinion a 1000times nicer finish and all it lacks is a "JEM Series" sticker on the headstock.
i repeat THAT'S MY PERSONAL TASTE! I understand that lots of you prefer different setups, that's why there's so many guitars around right
this is a signature RG that has more to offer than just some finish and name stickers