I ran a 50 shot on my 89 TBI 2.5 for about a month. i borrowed my friends kit and ran 1 bottle through it. I was trying to decide if it would be worth the money or not and testing it out in real world crap was the best way to make the decision...
in the mud, AWESOME... got my wheel speed up and cleaned the boggers well.
in BIG rocks, helpful bc i could romp on it and heat the tires enought o really grab the slick rock face.
in SMALL rocks, don't... you'll just break axle shafts if you try to use it to get out of a bind and if you're not in a bind you will just throw rocks... useless.
on the street, helpful i guess.... i didnt intend to use it on the street, but i did a few times. used it mainly on the highway to pass and it was helpful, but i could have passed without it if i had a little more passing time. raced my neighbor's '01 2.5 on 35's with 4.88 gearing off the line and spanked that ass. we ran from 0-50 (speed limit 45). it felt great to beat him by 2 lenths with big mud tires and a shiny blue bottle :)
overall, bo-yah! it. i could have gotten the whole kit (wet NOS) for $250 with a 10 lb bottle and decided the money would be better put toward a 350 swap b/c we all know we wouldn't be stuck with the 4 pissed off squirrels if we had a ton of money sitting in the bank and a plethora of LS7 engines at our disposal :)