Sound is great, sounds more like a Ferrari or Maserati
There are a few on board videos of me with my GHL on YouTube (look for ChrisZang), example
http://www.youtube.com/watch?v=L9nsWLBFKrY
A nice side effect is that the rear trunk will be less hot as there is more air flowing around the muffler to cool it.
Resonance between 2k and 3k is loud, I mean LOUD, I always keep the revs over 3k
It's actually so LOUD that my wife is no longer willing to keep up with the volume in the car, so the GHL must go
, send me a private message if you're interested