how does the borla cat back system compare to racing beat? just how much muffling can I expect

 

If by muffling, you mean less Decibels? I like Racingbeat's because they're a legendary rotary company and it's quite loud (Not cherry bomb coffee cans). The Borla ones that I've seen on various other vehicles tune the noise to be slightly lower in pitch; thus, making a lower noise. Both systems you can expect the Decibels to be quite large...

 

I have the Borla catback on my car and it sounds amazing. Im running a RP racepipe also, so there are no cats and it is still pretty reserved at low RPM. Its actually really low compated to a lot of catback and looks almost stock. Here is a clip of my car. It was taken on a digi camera, so sounds isnt great, but you can tell how it isnt raspy at all.

http://www.youtube.com/watch?v=UzgBMyRjiaI