OK If you are open to learning.............
Of course I'm into learning.
I didn't get five aviation ratings by being a "closed book." Two of those ratings are commercial.
With all due respect, and I know this Epoxy VS. Polyester thing has been going on for a long while.
I've always been lead to believe that Epoxy is heavier. And lead by some informed individuals. I cannot change my mind on this. Well, maybe.
Polyester, the ratio mix is more forgiving than that of Epoxy. By far. This you know is true.
I know the Byron kits well, having had a few and don't forget Mr. G's kits. I had two of them. Issues were developed because builders used glue products that wouldn't stick that well. Even today, that problem still exists. It's the builder, not the material.
Brittle / Flexible. Well, read this.
1997, Fiberglass Specialities catalog. Says right on the cover, "New FLEXIBLE epoxy." I could photograph it.
Not that I don't want to learn, to the contrary.
I'll stay with my winning game, Polyester.
Although, this I must say. Years ago, I purchased a set of Gee Bee Z wheel pants from Stan's Fiberglass. Epoxy they are. And they are excellent!