I could get the 330i BMW Performance rear brake kit to fit to my 325i. I believe I'd have to modify part of the handbrake.
However, the 330i BP rear kit is out of stock & would take approx 5 - 6 weeks to have it. I'm not sure if i want the rear brake now since it's gonna cost $1200 & the wait is forever.
So, I decided to give my stock rear brake calipers a little cosmetic treatment:
Re-surfaced & painted to match with the front. (Sorry for the bad quality pictures).
Ohh, the front wheels now have just got Macht Schnell 15mm spacers (previously 5mm) & I'm content with the new minor improvement.