I found the 'thornproof' tubes way too heavy. I have tried the Blackburn slime tubes with mixed results. Most of my flats are pinch flats and the slime does nothing for them. I have been through 3 on the rear, but still using the original on the front (after patching it once). The good thing about the slime is that even if it does go down, if the hole is small enough you can just pump it up and spin it to spread the slime and away you go. Doesn't always work unfortunately. The other thing that puzzles me about these tubes is that they are marked 1.5-2.2 but only look like 1.5, thus in a 2.2 they would have to stretch an awful lot. Seems like too big of a size range to me. I have also tried the liners without much success, and oh what a pain to install!