So no droning? I worked with rich/MadDad when they initially developed the mids (for the 135i), and the reason they added the small 'resonators' was because they found straight pipes introduced drone.
2011 BMW E82 1///M: AW, all options; Renntech, Akrapovic, Forge, P3, RevoZ CF bits, many mods
1988 BMW E30 M3: Hennarot, S14, stock
2016 Porsche 981 GT4: Guards Red, LWBS, SC, full leather
1998 Porsche 993 C4S: Zenith Blue, last aircooled widebody, Bilstein PSS10, Fister II + Fabspeed exhaust
2008 Audi B7 RS 4: Sprint Blue, Audi Exclusive Euro Bucket Interior, Premium+Titanium, many mods