well my dealer i bought the car from is teh roush dealer so I can use the rebate to purchase through roush the chip and intake and have the dealer install it all and not worry about warentees.
First off, dont waste your rebate money on a crap intake and tune..
Bamachips and Brenspeed are really the only way to go
As for the warrantie.. Intake cant void your warranty work, and with the tune just return it to stock when you take it in ! I live in cali. were most of the Mechanic Nozzies live and I get away with just returning the tune back to a stock tune and no problems ever, they see the intake and even compliment me on it !