I must saw i'm happy that my design is just like the M5's setup.
Except the M5 has 80mm pipes.
i was planing on going 3''.
From Realoem.com F10 M5 exhaust
Current, i3 Capparis White, Lodge interior
Ex- F10 550i Xdrive M sport, white
Ex- trade-in 2008 E90 M3