Is AMAZING. I tried it out today, poured it on in my brake bleeder valve or whatever it's called. Started to sputter after the third, So I went ahead and shut it off. I knew it was gonna smoke, but it smoked like a S.O.B. The whole front yard was engulfed in smoke, and somebody left the garage open. Sucks for them.
Went and did some hard acceleration runs and cleared that puppy out. I thought that that was an awful lot of crap... So I had my friend kyle come over, and we poured another third into his 2000 jeep cherokee sport with the 4.0.
It only has about 70k, and was owned by a dealer's son, so it was very well maintained. After waiting a few minutes, it had hardly smoked at all.
I was almost disappointed at how much gunk was cleared out, shows how much it was neglected.
Overall I am impressed, I don't really feel much of a difference in responsiveness but it idles a lot smoother for sure. Not really lopey anymore.