it sets up reasonably flexible, not brittle at all but not "soft" either. I don't know of other brands...I've seen several variations for specialty uses (a la "Shoe Goo") and suspect they're all the same product, but not sure. It's about the consistency of thick honey but can be thinned with, I think, acetone? Larry Renger may know for sure. I don't thin it. It is extremely tenacious and inert stuff.
--Ray