RE: Polycrylic vs epoxy for glass cloth finishing
I used it on my TF Cessna 182. According to forum member 'Campy', the poly will do the same job as epoxy, with a 40% less weight gain, and it tends to dent easier than an epoxy surface. I've never used epoxy on a complete fiberglass job, so I can't compare. I can tell you that from bare balsa to painted and finished added less than a pound on my 182.
As far as strength goes, it comes from the fiberglass, not the epoxy. If you can get fiberglass to stick with snot, it should still be plenty strong.