They are so damn expensive! I suppose it would be wishfull thinking that there are replica's out there already for these (as seen in this link)
I ordered some Dunlop M3 RF from tirerack and figured I'd save some $$ on the package ($2900 CAD), however the dealer isn't really discounting much off the package (suggesting they have to buy the wheel and tire combined from BMW Canada that way). I may wind up giving back the Dunlops's (or selling them) and just getting the package. I don't really like any of the aftermarkets I've seen so far that fit (even ordered some M5 replica's, but after seeing them on a friends car in person I wasn't all that impressed).