Ive got an rb25 turbo on my r32 and it made 195rwkw @14psi on a 31deg day. I have similar mods to you but i have a chip remap, boost controller and cam gears.
I used to have a video of some guys that strapped a duck caller to their wrx bov and it sounded hilarious. They drive around in traffic with it on too.
Personally i don't think a cat back does squat in term of performance. It's like putting a fire hose on the end of a garden hose, it don't make the water come out any faster.
Hehe a cop pulled me over once and told me to move my front number plate into the middle of the bumper, It was on the side. He said it wouldnt block my radiator pointing at my cooler. I just said , yep no worries.
I run 14 psi through my rb25 turbo all day every day. I hasnt blown up. I ran 1bar through my rb20 turbo for over a year and it didnt die either. People are too wussy these days.