Hi there,

There seems to be some myths about epoxy. True is that, there are three main disadvantages:
-You have to keep the mixing ratio exactly
-The ambient temperature has to be high enough (typically 15°) while epoxy is curing
-It is expensive

On the other side:
-no osmose
-much tougher than any polyester resin or gelcoat (no hair cracks anymore)
-can be used as gelcoat as well
-usable with high quality fibres as kevlar.

If you use polyester, the resin will always fail before the fibres at very low stress. However, it is sufficient for normal usage of beach cats. Epoxy allows to use the full potential of fibres and it has more abraison resistance.
I never had the problem with sticky epoxy due to sunshine. Cold hardened epoxy is stable until about 60°C. Shouldn't be a problem until you paint your boat black.

However I would choose polyester and glas due to the easy handling. If you have a good workshop (closed, not to cold), there is no other disadvantage than the costs, but the boat will definetly be stronger. I would not use kevlar, it is simply to expensive.

Cheers,

Klaus