I like my stacks, I didn't think I would at first but I do now. The noise ain't that bad, and I don't really get a drone until I hit about 70MPH, but it sounds really good when your on the outside
I had the PPE for a while, and it worked great, but then I decided to upgrade to the FASS, but if your working on a budget then the PPE is a great buy. The only downside is like what Kyle said it doesn't come with the hardware to install it.
Personally I like stacks but, their not for everyone. My dad has the 5" MBRP exhaust on his LBZ and he likes it. I know its overkill but it looks good, and sounds good