Latest update:

Seems to sand well, but has a low melting point (120F / 54C ) so sanding should be slow and light. I sanded from 600 to 2000, EEE and then a plastic polish. Looks good. Might just be a viable alternative to expensive finishes, but I'll do another one and give it to someone to put it through the paces and see how it holds up in the real world.

I just tried it on two pen bodies, and so far it looks like thin coat is the way to go. It has about a half hour open time before it starts to set up, so I'd apply it to the wood at the END of that time. (5 minutes mix, 25 minutes working time). I put one on early and another at the end. The early one stayed under the lights on a slow running lathe. Toward the end of the working time, a bulge was visible around the middle of one half, I could see it rotating under the lights. I just put my fingertip to it and it came off.

The nicest part? It's self levelling and gap filling!
And it should be hard and durable (it's a bar top finish)

The down side? 72 hour cure time.