I see some guys with 5 inch exhausts and no muffler and wonder how they do not get VI'd.. But yea i dont think you're going to pull somthing like that over a comercial inspector, Maybe the odd cop, its just going to keep getting tuffer too, i saw a clip on the news the other day of a diesel smoking out another car and them saying that it is causing lung caner, Not long and they will throw in some more sever regulations for diesels.