Ugggh- just went around the block to test some more and it's flat out AWFUL.
This can't be right. I'm guessing that one or both of the cats have internals that have come loose in some way. There are no leaks, I'm 100% certain and incredibly anal about using proper torque specs and procedures. Even used brand new gaskets for the header to cat pipe connection.
I paid good money for these pipes, too - if they are buggered, there's no warranty for them.
I just don't think this is how it's supposed to sound. I had my wife do a few drive bys so I could listen outside, and it does, in fact, sound "broken" as she stated flatly.
I've asked the fine gents at AWE if I can send them in (my shipping costs) to have them diagnosed. Either way, they're coming off the car and it'd be a shame to just toss them in the closet.