I cant say about the Bixlers Toobseal, but after having my own 9 ft. Hypalon Caribe professionally patched, I was told that I might still have to pump it up each week, which turned out to be every 4-5 days or so. When I told them about it they recommended this stuff from West Marine, saying it was very effective if applied as instructed. I got the stuff that afternoon and squeezed about a cup worth into each valve. After reading your post, I went up to the boat deck and reached over the davits to feel the tubes. Hard as a rock!!! and that's been for 10 days now. Here's a snapshot of the product. Very happy!