I agree, Melee was great, you 'd have to play quite a long time to unlock all the characters, modes, levels, songs and trophies. Hell, I enjoy the fact that they keep a record of the date and time you unlock each item and first beat each level.
Orta has some great un-lockables too, but I was fairly dissapointed to find out that eventually they are all unlocked when you play long enough. I like to accomplish something besides persistance to unlock an extra.
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