I don't know any info about that particular exhaust. However I'm running a gutted cat and 3" cat-back Ebay exhaust on my RB20 and it sounds very, very nice

The piping is straight through, even the muffler (so I doubt it's doing much muffling). I love the sound of it though. It's very distinctive but I'm not quite sure how to describe it. The only part I can describe is the loud bang when this thing backfires, which it does quite often

Heck sometimes when I rev it at idle small flames come out the back. Now I just need a 3" downpipe to finish off the package.