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.
Yes, as long as the minimum amount of MEKP is added you can go 3 or 4 times the amount and all you do is shrorten pot life. That being said, you must still measure out the MEKP so you get the same ratio throughout the layup. If not you have differnt expansion/contraction rates. Imagine a fuse with this happening differently on each side.
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.
Byron was suggesting epoxy to bond in formers and such and not instructing on how to properly prep the surface. Once instructed to scuff with 100 grit, clean with acetone and bond in with polyester and 1" glass tape problem was solved. Until some thought it was OK to glass wings with the same resin.
Brittle / Flexible. Well, read this.
1997, Fiberglass Specialities catalog. Says right on the cover, "New FLEXIBLE epoxy." I could photograph it.
There are all types of hardeners that modify the finished product
. If bonding in a high vibration enviroment, this would be a good way of going. Dosen't really apply to this topic as it is not laminating resin
Not that I don't want to learn, to the contrary.
I'll stay with my winning game, Polyester.
If you are happy with the results you are getting why change. Different people have different expectations. Building composite components for a DOD company have raised my expectations and it has helped me build better models.
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!