I'm split. SMRPG was always my favorite, but PM improved on it it just about every way -- and yet SMRPG is still the only one I can never get tired of. SS is close, but the story drags it down (the least cohesive out of the six; it often feels like they were just making it up as they went along). For the first playthrough, SPM was the best, but that's not on the list anyway (It should be, though. Debates about the nature of RPGs in general aside, it is a Mario RPG, being a natural evolution of the Paper Mario series. Whether or not you call it an RPG, it's the only classification it fits in the Mario series.).