I say get them, I have the st-60's 355mm and required 3mm spacers to clear Rennform 18x8 ET45mm.
My experience is MPSS do give out before the brakes, more so when they aren't warm, but you soon appreciate the reassuring feeling of relentlessly effective stopping power that seemingly improves the more frequently you roll onto the middle peddle to stop 3000lbs at 3 digit speeds.
PP brakes are excellent street brakes, but there is no getting away from the fact they fade.
Looks sweet. Looks like then that needing spacers would be the case with the 18" VWR wheels considering they are similar dimensions (18x8 with 45 offset). If I could get away with 18's, I will. Much more driveable and just looks better with the bbk.