Thanks for the comments. In regards to a dual exhaust system, I changed the stock system on my Concorde LXI and my fuel mileage changed from 26 MPG to 30 MPG overnight, and the noise in a non-issue. The cats would remain for emmission standards. I guess I'll have to go with a custom set-up.
Too bad about cold-air intakes, I guess it will just take time.
I too have read the reviews on the chips.