I'm a tried and true Mario player,and with my limited tourney experience, I have to agree with everything Gea has said about Doc being slightly better. Pill rushing and that F-Air do alot to Mario that has trouble killing.
However Gea, you said you'd rather choose Mario in match-up aganist Peach. Not trying to go off topic here, but as I constantly am stuck fighting Peachs, that has me rather confused you'd choose him over Doc.
Is his limited recovery outweighed the fact of him being easier to KO off the top easier with the FAir? That's the main reason that bugs me, although there's bound to be more stuff I can't think of at the moment.