Here's a some tips:
- avoid Luigi's Mansion like the plague.
- when first starting a match, the first thing you need to do is spot dodge. This avoids the common first laser beam.
- dairing ROB is quite easy.
If your area is playing with Luigi's mansion as a legitimate counter-pick, you need to petition or whatever to get it banned. Many communities have it banned simply due to it being another Hyrule and the fact that Meta Knight is broken as **** there.
As for the actual matchup, throw lots of turnips while floating, use d-air a lot, fair ***** him, and don't try to hit him when you're underneath, his priority is too good with nair and dair.
otherwise, toad the obvious nairs - if he's campy, turnip -> fair pressure / d-air.
if he's aggressive then you should be cautious or be really good at spacing fair.
moves to watch out for: spotdodge -> dsmash, bair, nair, fair, upsmash.
i find the best ways to kill him are charging upsmashes after he spams spot dodge - a lot of robs i've played like to roll after they spot dodge. they roll right into it.
im pretty sure peach beats rob in the end, i don't really see the advantage for him. although his spike is **** but obvious, so don't get hit by that.
edit: im gonna probably start posting in this matchup thread a bit more, simply because im playing peach a lot more these days. melee peach and brawl peach felt similar and while edrees's melee peach ***** mine i'm no slump with that ****. man, i should post the peach dittos niko k and i have. theyre epic ****. actually entertaining brawl vids.