Hey Anand, can you give the name of one of the Cali BAR places that do the test? I'm in the SoCal area also - I'll try to do a search for a place like that myself too. I want to do that w/ my Trust exhaust. It's not that loud in the first place and cops haven't pulled me over for it yet, but I want to shut my gf's neighbors up about my exhaust being "too loud bla bla."
back to the subject:
In Cali, I believe there is no longer a set dB level for the cop to write you a ticket. It's up to him to "judge":
http://www.chp.ca.gov/html/streetlegal.html - so this may be for other states also
Also, when exhausts are mentioned as 50 state legal, that has nothing to do with emissions, and exhausts don't usually affect emissions anyway from what I remember. The exhaust itself will be under 95db as 50 state legal, but that doesn't cover anything about headers + intakes, etc.
But yes, fight it, fight it with all your might. From what I've learned from other members on this board, one idea is instead of fighting for many minutes and hours with the cop up front, just be polite and take his sh*t. If you fight him then, things could just get worse and he can just write even more bullsh*t tickets. Then get all your stuff together (paperwork, etc) and take it to court.