You get what you pay for! If I was staying with in the warranty and didn't car about the NPP valves I would do what my friend did.. we installed the Corsa Axle back at my shop.. Then Phastek did the Borla X pipe.. (because it wasn't loud enough!) it's a little louder and deeper now and retains the cats.
If warranty isn't an issue headers and Borla Atak.. the great thing on the Borla you still have the Valves to control where as Corsa doesn't.. I have a friend that had the 1st stainless works setup Headers and catback.. he didn't like it drone and wasn't the right sound for him he liked my wifes car much better( Borla headers and Borla Atak).
I've heard Flow Masters from several 6 gen in Houston they sound ok at full throttle but lack it at idle.. sounds like a boat exhaust dipping in and out of the water.. if you been around boats you will get it..
The phastek shop car sound is pretty good with that MBRP...
The point is "Well I have been using Borla since, long before my wifes car was the R&D car for the 6gen" lol I sound like Mathew in the MKZ commercials..
No I have had borla on my 96 z28, my 2010, 2016, and shortly the 17 zl1 with carbon tips..
Borla takes great pride in sound and performance I had a chance to do a episode as well on All girls garage.. They went with another SS because they know that a blower on a car will have different sound than a SS will amunce other things.. infact take a gander at other companies most list the same part numbers for a ZL1 or SS.. That's how much Borla cares about there products.. There is a product designed for each model and unique sound not a 1 fit all exhaust.
BTW I run headers and stock NPP for now... it's driving me crazy not to sound as good as the wife's car.. I would bet anyone that she has the loudest 6 gen in the nation that's not cammed and has mufflers.. it's not only loud but sounds good to..
Windy day at the track with a small phone mic.. there is also one from sealy 1/4 mile track thumb through my public channels... the most interesting is the loudness at Texas motor speed way at the end of the video.. loudest car there!