I thought about a glass pack before I put straight pipes on, they said that a glasspack would not be as deep and perform as well. Then bewteen a cat-back and a straight pipe set up, the straight pipes are the best(I had a flowmaster cat back), but only if you can get away with it your state. In colorado the police have much more on there minds than our trucks. Plus most of the po po's I know they knock my truck out of the mudhole.