Hehe yeah, I'm actually having a new muffler installed to quiet her down a bit. With the UR system, Extend the rear tips buy 50mm and half the in car noise disappears.
I dont have the Dump pipe too, only the high flow metal substrate cat back system with resonator.
The dump pipe and Cat might give you 1-2kw ATW but thats all, But your turbo will flow better and not get as hot as there is less resistance.
So get the UR System, Approx $1700 Delivered from Canada, Get the Resonator and Mini Muffler and have the tips extended when you have it fitted. The not this system makes is amazing, but very loud out of the box.
The HKS Approx $1600 for a Cat back system. Brilliant quality, a little quiet for my liking but still a deep solid note. In cabin noise was close to the OEM system.
I've had both on my car and both are good systems, You just have to decide if you want noise or not
Feel free to ask many any more questions about these systems.
Good luck with your choice!