What are the optional wheel sizes for the 435xi M Sport

First I would recommend to use the tire size in the door jamb. These are set by the car maker and your Ins. Co. would have a bad news if you were to get in a accident and they caught it.. Just saying.......

If they are the same.......No Problem,a different style Rim "Looks" is fine.

the only problem you might ever have with an insurance company is if you put a lower speed rated tire on your vehicle than it originally came with. your best answer for this question would be on a site dedicated to sports car enthusiasts and even specializing in bmw's would be better. there are too many people on this site trying to answer questions about car customizing that don't know anything about it and want to convince you it's a bad thing because they are afraid.