Originally Posted by ferrari4evr1
Ouch! In that case, I think if the 1M exaust is in that neighborhood, you might as well stick with the stock? Stock sounds good too.... Not sure it would be worth $5-6K just for a 12hp increase and a slightly different sound note...
Best bang for the buck, and likely sound, would be to stay stock as far as rear cans, and just replace the midpipe with MadDad or the like. So far it has been speculated that it is just the end quad that is different on the 1///M, all else same as the 135i, so the aftermarket midpipe for $500 or thereabouts would give you some nice sound, modest gains, and weight reduction.
2011 BMW E82 1///M: AW, all options; Renntech, Akrapovic, Forge, P3, RevoZ CF bits, many mods
1988 BMW E30 M3: Lachssilber on Silver, Dinan S14, 17' BBS rims, stock
2016 Porsche 981 GT4: Sapphire Blue, Factory bits, Xpel, stock
1998 Porsche 993 C4S: Zenith Blue, last aircooled widebody, Bilstein PSS10, Fister exhaust, mostly stock
2008 Audi B7 RS 4: Sprint Blue, Audi Exclusive Euro Bucket Interior, Premium+Titanium, many mods