Mechanics apply with in

Only reason im even considering the internal sealer method is to limp me along till I either find something I want to buy or decide to fix it. Its been a pretty good truck for 6 years now. Its got some rust and isnt perfect but I wonder if its time to let it go.

Blue Devil from Napa.
It is 60 bucks, and is supposed to be the best stuff. I have heard 2nd hand, that a friend has used it on several vehicles and it has run for several years. I don't know how severe, but it is rumored to be guaranteed, or money back.

I have a bottle in my truck for a niece's car. She is broke college student, and it is either Blue Devil, or JY for the car, because of finances, so we are going to give it a shot.