I currently have a NP 5" muffler axle back for my 2011 WRX sedan. I'm looking to get the NP down-pipe as well, which is 3" in diameter. From there I'd like to get a mid/y-pipe, but IMO 600$ is way too much for to pay for it. Have a friend with a shop who has offered to make me one with SS. Would getting the NP DP -> custom mid/Y -> NP axle back be a good set up? Does anyone have this? I was thinking of putting in a resonator in the mid to help tone it out with the expansion to 3"