Have a M Performance Exhaust (18-30-2-464-492) on my m340i I bought in January 2021. Originally bought for around 1900 from BMWPartsWorldWide and can provide original receipt. I have to turn in the car in a couple months so figure I could swap the original exhaust back on. No issues, works great on a 2020 and is quite loud. Note subsequent model years will not be as loud.
Part compatibility:
-G20 - M340i-ix
-G20 LCI - M340i-ix
-G22/G23 - M440i-ix
-G26 - M440i-ix Gran-Coupe
Located in Sugar Land, TX (near south Houston)