In was going to get Godspeed for mine before I sold it - spoke to Ian Godney about the kit, he reckons the 4 pot Subaru calipers are actually quite good - just need a bigger contact area - speak to Ricey he has had it for years on his car. He said it was great.
AP's will fit under your 17's Stephen - that was also an (expensive) option.
I'd go Godspeed - the Brembo's are pretty overpriced often and I liked the standard WRX wheels.
Brian []