Omega,
I really have no idea, but I can tell you this: Any aftermarket company that deals directly with a particular manufacturer (Yoshimura, Muzzy, Erion, Feracci etc.)has information/developement assistance that NO ONE else has, for that brand.
The Japanese, in particular, are VERY specific as to who recieves info.(The sections of my 1999 drag race agreement with American Suzuki that relate to divulging sensitive information are valid....FOR LIFE!)
What this means to you is that it is very hard to go wrong with these companys.
You generally recieve a product that works very well for the application which it was designed.
For special applications you should find a racer that does well in the area you are interested in and ask what they do or who they work with.(For instance, I use Yoshimura road race products for drag racing and severe street applications because they were designed for longivity. Some drag race products were designed for short term use.)
Most of these companys do have products for other brands(Yosh pipes for blackbirds, Muzzy pipes for hayabusa etc) these normally boil down to personal preference or experience, test results,etc.
Other products; ignition boxes,cams,jet kits,mapping systems,etc. are usually derived from racing or developed in Japan with assistance from the factory. These products are second to none for nearly all street applications!
BIG HP or non-typical applications require aftermarket cures: Dynojet PC2,Sudco, WEB, APE, SCHNITZ, Orient Express,etc.
I know your question did not get answered directly...but I hope you feel better about your decision.
Brock
