I'm not sure on the BC percentage of PS3's, but the EU 60GB one (which has the 80GB American BC in it) seems to play pretty much everything I own (~50 PS2 games, one or two don't work). I should check though - SSX tricky didn't work when I first bought it, perhaps it works now.
(One can only hope :P)
I've not recently checked the Xbox 360's BC because I sold/gave away all my Xbox 1 titles that didn't work a few months back.