On the Hellcat, the wood parts got one brushed coat of 20 minute finish cure epoxy, thinned 150% with methanol. The foam wings were covered with silkspan, then SLC covering. The airplane was sanded and sprayed with Superpoxy primer. I mixed up one 8 oz cup of primer, and sprayed until the cup was empty. On the wings, I only primed the fillets, tips, and covering seams. Then, I applied one good coat of color. After I screwed that up, I sanded the finish and gave it one more coat, just enough to cover. It took less than 4 oz of color. Rather than risk another mishap, I will apply stick-on vinyl trim, then clear coat everything. This was meant to be a "utility" finish, so I didn't care about completely filling the grain, just sealing everything. It turned out better than I was expecting, no doubt in part due to the extra coat of color.
On last year's Zeros, the wood parts were glassed with 3/4 oz cloth and finish cure, and the built up wings were polyspan applied and sealed with nitrate. They were also primed with Superpoxy primer and painted with Klasskote color. The glass cloth gave a better finish, but it was quite a bit more work.
For now I still have a decent stash of Superpoxy primer, but if and when I use it up, I will try Klasskote's primer. If it's as good as Superpoxy primer, I will be a happy camper!