whoopee on your observations bents.
after working with polyester and epoxy full time for a few decades i could probably state that both are bluddy nasty poisons and the warnings on the labels are more than true: eg, avoid contact with skin, don't breath the vapour!
customers to my shop used to comment (even with the exhaust fans on ) that the fumes from both, made them feel faint and nauseated, and i used to comment that i couldn't even smell what they were talking about!

i developed bad dermatitus even after wearing full protective suits and panelbeating industry standard isocyonate vapour respiration masks.
having said that, epoxy is the gun resin of the future, available in a myriad of different concoctions for heaps of applications, it's a tuneable medium!
unlike polyester which is boring, brittle and still turns out a cheap fishing boat.