Does anyone have any exp. or input with this "kit". I was looking into it for my 94 Suburban w-7.4. Did it improve performance much? etc. Thanks.

 

There's a couple guys over at Fullsizechevy.com that have it and from what it sounds like is that it isn't really worth the money. They say throttle response is a little better, and gas mileage is basically the same maybe 1-2 better if that.
I've heard more problems than benefits with this setup.
Definatly do more researching on it before you make your decision.