I really enjoy my sonic. but a few things have came to mind. I really am thinking of putting a ddm works exhaust system on. A few questions... I dont want to void my warranty for any systems. So the question how does the Cat back systems fit on. Keeping the old system around if anything was to go wrong could i swap out easy?. Also.. Im taking it in for warranty work because when i get on it and shift 1st to 2nd quickly it grinds every time. Now ive drivin straight shift in every car ive owned so my ability to drive a straight shift is not in question. Im thinking a linkage issue. Anyone else have this problem?