In the most recent (Feburary) issue of Motorcycle Consumer News, journalist David Searle provided the following response to a question regarding tire sealants (slime):
"I tested tire sealants many years ago for Road Rider (our predecessor), and found that the stuff actually prevents accurate balancing, quite the opposite of the "self balancing" claims. Also, the stuff will corrode aluminum rims, occasionally to the point of destruction of the bead sealing surfaces (requiring wheel replacement). The gunk is also a big labor job to remove when changing tires, which adds to shop charges. Also, oddly, all of the several different brands of sealant products we checked were traced to the same manufacturing facility. Since that time, I don't recommend them."
Thought you might be interested.