I love 'em all... I don't know why, though, but I find it kind of hard to get into SMB3. I really have no idea, it seems just like the sort of Mario action I'd be interested in...
While the other two, I've loved to death. I first played the original on the Game Boy Color Deluxe version, and kept it with me pretty much all day. While I first played Two and Three on the Virtual Console... I was ferociously determined to beat Two, and I did. Then, I managed to beat Two again using no-one but Toad (It wasn't THAT hard...) I did beat Three, too, but I never really felt like playing it again for some reason. Weird... I do like it very much.
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