I tried it. It's shipped as a powder and mixed with water before use. It looks orange when mixed and is very runny, so it slops on quick.
At first the wood doesn't look any different. After a few months, it starts to look weathered. I still do see a little mildew on corners but I live in Florida the humidity capital of the western world.
After 2 years, next to crip white hives, they look a bit grubby - def. the ol' barn wood look. But if all were the same, and the purpose is only an easier upkeep, I'd have to admit I haven't painted those nuc boxes in 2 years. :)