For a DD and too be relatively livable I will recommend the 18" resonators 100% and would also say add Carbon Fiber because this makes the exhaust note deeper and more exotic versus Stainless steel. It's quiet when you want it to be and will scream as well when needed.
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|2013 Audi S4|Ibis White/Black|S-Tronic P+|
|2013 370z|PearlWhite/Persimmon|Touring/Sport/Nav|F.I. CBE 18" CF|
|Sold|2011 370z|Gun Metallic|Touring/Sport/Nav|
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