anything i should know before buying this stuff?

and, as requested in the other posts, any pics of that vacuum line? or advice on finding the line?

also, is this better than the fuel additive stuff i've used before? sounds like seafoam is part maintenance, part religion
this isn't quite what i've used but its basically the same. i have some of this laying around too, that i might try (the stuff i had was extremely generic and cheap, it was just the first i saw at the parts store, and i was in a hurry.)