Doesn't look durable at all - but it's extremely durable. I use it a lot as a substitute for epoxy on baitfish imitations to hold the stickon eyes in place.
I don't use it in place of epoxy for poppers and sliders though, these do better with the hardcoat.
Epoxy yellows due to imperfect mixtures and UV rays, Softex doesn't.
Each has it's place... but boy they both stink! Phew!