OK, then from Facebook if this is not just a promotional photo...it's dated April 18th.

 

Went to check this GT4 out at Vancouver Porsche last week. It was on the rooftop and they cold started it for me to hear the exhaust. Way louder than I expected after reading so much about the filters, at least for startup and initial cold idle.

 

This is the one. Owner didn't pick it up and its available....FYI!

And I too also listened to the exhaust and revved it up with the valves open; its loud...i think the sound issues may be a bit overblown. Won't know for sure until its driven, and you hear in the cockpit of course. Still don't know if there is a OPF or its there but just a blank...