Originally Posted by Uncle Scotty
and yer gunna hafta buy spacers and any spacer more than 5mm you will have to get new lug studs and 20 new lug studs aint cheap and ya gotta pull the hubs to put longer studs in and so if ya dont do that work yourself ya gonna have to pay and ya gotta change the bearing seals so ya gotta buy them too and on and on and on and on
He could buy bolt-on spacers, in which case none of that would be necessary. I think on an '06 WRX that 20-25mm bolt-on spacers would work OK with those wheels. (Even with a 25mm spacer, the outer lip of the wheel would be 1/4" inboard of where a 17x9" +42 wheel sits.)
I don't know if those wheels have pockets in the mounting face between the lug stud holes to allow the stock wheel studs to poke through.