Agree.
If you have a shop around that can make you a custom one, go there.
If you ask about the sound or looks...as it has been said before, that is subjective, you have to choose for yourself what you like.
If you are asking from the performance point of wiev, that's another story.
For a turbo you cannot go to big. As a matter of fact you can vent it to the atmosphere as soon as you can (see the cars with exhaust pipes comming out on the sides of the vehicle, right after the wheels).
For a N/A it's another story. This ones need some backpressure for the engine to work right, so a well documented and studyed exhaust is what you should look for.
I personally have a 3" BIC divorced downpipe replica, that starts from the turbo (the stock elbow has gone). No cat or anything else, just plain 3" stainless steel to the Borla ending the exhaust system.
What can I tell you... It is loud, especially under full boost, when the weastgate vents directly to the atmosphere, but it revs a LOT faster.
Also here are not such strict regulations about emissions, so no wories there.
Hope I helped. When I get to a PC (I mainly enter from my mobile phone), i'll post some pictures.
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