I have a Optimus Performance Axle back exhaust on my 2014 infiniti Q50 premium. It is resonated with burnt tips (blue) . bought it for 425 a few month ago will take 350.
Sound is very nice and deep specially when you are on it. Definitely a head turner. And it looks really nice. My wife can't handle it so I'm taking it off.
Local sale preferably
Houston, TX