Thanks guys. It's definitely a bit different. Still getting used to the new tone. Higher rpm shifts--over 4000 rpm--in S5 have a more pronounced character to them.
I understand what M3PO is saying about the jumps in sound. They come on pretty aggressively when they come on. For sure, having more "stuff" in the way of the air smoothes things out.
My friend listened and compared, and said it sounded like the stock exhaust had a pillow in front of it, and that the test pipe sounded like the pillow had been removed. He liked the test pipe.
Everyone has a different perception. I love that about sound.