I slime! I have had to air up more than once for it to work once or twice, but when I finally blew out a tire, I found many little slime balls on the outside of the inner tube, where slime had been doing it's job!

I also use a liner, mr. tuffy brand, i think. When I started commuting this time, I weighed 270 lbs. and had 4 rear tire flats in 4 days... so I slime!