LabRat,
BPM was very clear on the gain differences when I purchased my TT. They said the the gains would be much less with the TT (8-11HP)and that is about what I saw. I wanted the twin tip so I went with fewr HP to get the look that I wanted. I wish I was in CA, because I would love to race another WRX and I would love to see the difference between the two mufflers. I am also curious about the noise factor. Mine is very quiet at speed, in fact you can't even hear it at 141.
Curt
[This message has been edited by Turbo4me (edited June 03, 2001).]