I don't know how UMvC3 ended up, I just remember there being a lot of discussion of poor sales at the time
stuff like
http://www.siliconera.com/2012/02/06/ultimate-marvel-vs-capcom-3-sales-slower-than-super-street-fighter-iv/
http://gotgame.com/2011/11/29/ultimate-marvel-vs-capcom-3-sells-poorly-has-clever-joke-made-at-its-expense/
SFxT I haven't seen any numbers, that's just what I was hearing from the SRK forums. could be completely wrong!
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http://www.youtube.com/watch?v=npHDxSvwCE0