As I sent a note to EvoGuy, I am working on a CAT and back setup that is incorporating one of two exhausts at this point [Borla and MagnaFlow]. I have looked at the various euro exhausts and frankly they do not offer any value add to the mix. All they are is a XXXXX stock exhaust box with model specific fitments welded on the front and back to make installation easy to a specific form factor. Any of the aftermarket manufacturers [euro or domestic] have sufficient model sizes to provide a competent person with the ability to size up their car.
Once I get this system mounted up and dyno'ed again I will post model numbers of the "stock" parts. The big bogie is the bent pipe in the middle from the CAT to the EXHAUST if you remove the resonator [which I find makes a better sound, less restriction and saves some weight]. I will be making up about two dozen of those pipes, mandrel bent in stainless steel to make fitment easier for folks to either DIY or take to a shop.
I dyno tested a 3" diameter connector pipe with the high performance CATS and Borla EXHAUST and, while got a great growl, was disappointed with the torque band. I am recutting/bending a 2.5" pipe in the next couple of weeks to retest the car. I expect that the low end torque will increase across the band [picking up earlier]. For those wanting to run Bonneville and need the 175MPH top end, the 3" pipe would be YOUR better choice
Updates, recommended part numbers [borla v magnaflow] and availability of connector pipe as soon as they become available.