Will These wheels work with my 08 535xi?
 

Set of 4 Alloy Wheels oz Racing Ultraleggera 8x18 5x120 ET34 | eBay

ebay item:
122052106963

Description: OZ Racing ULTRALEGGERA - 8x18 / 5x120 / ET34

My car has these right now: BMW wheel style 243 | BmwStyleWheels.com

17 inch by 7.5 inch ET43 (offset) 5x120

Would appreciate help understanding this. So far I've figured that I can go with a smaller ET but not bigger. I'd guess the smaller ET has to be within reason or I would need fender rolling... is that correct?

Yes and yes.. et34 is just about perfect for the front wheels the rear you can go more.. but in short you can definitely buy those and it would fit.

I have put 12mm spacers in my rear tires to widen it out and fill in the fenders more. I'm running 19x8 et 33