Just got done installing my SLP Longtubes, Loudmouth, and O/R X-Pipe. All I can say it WOW, it is unbelieveably LOUD!! It has a tinny sound right at 3000 rpm and just screams! I left town last night and my friend was sitting in his basement on the other side of town called to see if i was out driving around because he heard me. The install was a big PITA but with a little patience, it isn't impossible, the biggest problem is only being able to turn some of the bolts one notch at a time. It sounds awesome when you rev it up, but at WOT it is almost unbearable, but im 18 so its all good I installed them with 4.10's so i cant really tell which made the biggest difference, but it definately pulls a ton harder.
The only thing is they forgot to send O2 sensor simulators, and then sent me another set of O2 extenders instead, so now i have to call when they re-open and get it fixed. They should be taking care of the shipping because it was their mistake, so I'll let you guys know how it goes.