+1
It stays inside the tube and doesn't make a mess come time to change tires. If you get a puncture it seals it, so a little comes out of the tube, but that is the point isn't it?
Now in tubeless tires, it is messier than the yellow-green stuff in a newborn's diaper. It can etch aluminum wheels too. In a tube tire, so what?
The only time Slime actually
spews is if you slash the tire, in which case you're SOL anyways. Make sure that if you do use Slime you get the appropriate type, tube or tubeless. The tube version has better sealing qualities but is also slightly corrosive. The tubeless version works well too but is designed not to corrode aluminum and steel wheels. IMHO Slime only has a bad reputation because it proceeded Fix-A-Flat, which is an absolute joke. It doesn't work, it never fully inflates a tire and it
DESTROYS wheels. Because of Fix-A-Flat's reputation of being garbage Slime instantly became "known" for being just another awful mess that doesn't work. The fact is Slime is actually a really nice product and works quite well. I haven't had a flat on my bicycles in over 6 years.
Scottie