I don't support the California insanity, but I have a hard time feeling bad for shops that were tuning for catless DPs and installing them. It has always been illegal. Yes, it was not really enforced, but the rules were there. Like speeding on a road that everyone speeds, then getting pulled over one day; it sucks because it feels selective, but the reality is you were breaking the law and now you gotta pay. As far as I'm aware, tuners are still allowed to tune, they just can't defeat emissions channels and install non-compliant components. All the talk about not even being able to put in an intake or cat back is bullshit fear mongering - look at APR, stage 2 tunes and DPs are suddenly gone, but they're happily selling intakes, cat backs and stage 1 tunes, despite being a high profile company that no doubt has the eye of the EPA. This won't destroy our hobby, it'll just get a little more expensive and a lot cleaner. The only thing truly at risk is those of us with actual dedicated track cars that aren't registered for street use; they'll lose the ability to ignore emission controls for not a great reason, but they'll still be able to race.