I know this is not an exhaust thread but couldn't wait to drive her this am. Cold start is loud'ish, proportionate to diff with cold start on OEM set up.
I love it! Car is perfect. Look forward to comparing sound live with Dave in SD with full RPI. Still very classy IMO.
F10 30 Jahre M5/F80 30 Jahre M3
F82 M4 GTS
E36 M3 with S54 Swap/F22 M235 Dinan Stage 4
X15 X5 3.5i/03 Cooper S (Maxi Tuned +50bhp)
60 Impala (43k orig mi)