What about this
I have pacesetter LT's with true duals with an Xpipe and flo-pro twisters. I currently have cats, as well. There is not rasp at all on my setup, currently. It is also very, very deep. It's pretty loud, but not enough for me. I want to be able to hear it at idle over my stereo.
So I'll probably be removing the cats soon. Hope that helps you. 
