I didn't realize Fix a Flat was so bad for your valves and tubes. I stand corrected! I only have 11 left, and after they're used, I won't order any more. If Fix a Flat is no good, how about Slime? Anybody have any experiences with Slime? As I understand it, you squirt the Slime into the tube before you have a flat, and it makes any tube self-sealing.