Do let us know how the Flex Tape works out.

I have made an overnight repair with the Aqua Seal. Seems that a pair of hip boots was leaking at the upper sole edge of the boot. I simply applied a smear of the AquaSeal in the area (exterior) after the boot had dried off in the sun, and put the boots to use the next morning (was dry to the touch) and that was the end of that leak.