mbrp....i will get you some video clip of my truck with straight 4" no cat no muffler and post it up tomorrow. you really arent gaining anything unless you do the true 3" downpipe first. i gained 2mpg when i did mine, and noticeable power increase.
MBRPCrazyford, i would do a 4" system. i ran mine straight piped with stock exhaust for a little while and didn't like it near as much as i like my stacks. and as said before, you don't really get much of a gain until you do the 3" downpipe.
yeah, I'm just not sure I wanna spend the money right now. Zookie, your truck does sound good. Thanks for all the help guys. I really appreciate all the info. It really helps me make a decision!!