i like it with the cut out closed. always thought bmws should have a deeper tone. With it open, it sounds way too obnoxious to deal with everyday. How about in cabin sound?
E90 | ZPP | ZSP | ZCW | CA | 6FL | NAV | XENONS | 18x8.5 VB3s ET28/25
2011 JB F10 | ZPP | ZSP | ZCW | 6FL | NAV | 331s Square