In the bench build we’ve been working on (and are almost done with!), I used a slow-setting epoxy. Other than proper mixing, the most important part of using epoxy is to use the proper proportions. In this case it was 1:1, but other epoxies vary. The trick is trying to measure that out, especially with the low viscosity of this stuff.
I have found that the little measuring cups, such as come on cough syrup and the like, are the ideal vessel for most volumes of epoxy. They’re graduated, so you can easily measure properly, and they’re also meant to be disposable. Any container you use is pretty much a lost cause once you mix epoxy in it, but at a few pennies apiece, you can afford that with these little cups.
The next time you have to mix epoxy, give these a try, and I imagine that you’ll be pleased with the result.