Van's Super Secret Scenic Dope (
VSSD) is what I'm using right now to
cover trees and other woodsy findings. It is alot cheaper and all the materials can be found at your local hardware store so there is no wait time or expense for shipping.
But to give you somewhat of an answer for your original post: Sculpt or Coat is lovely but I use
Jaxsan 600 more regularly. you can tint it, paint it, it's durable yet flexible, water proof and cheaper than Sculpt or Coat. The only con I've ever heard about it is you cannot sand it since it has a rubbery finish once dry. You can get it in a 5 gal. (You can get Sculpt or Coat in 5 gal. quantities but no
theatre I've ever worked at has had 5 gal. in
stock I usually find the 1 gal. but I think that's more a price thing than anything else...)
Jaxsan is actually a roofing material so you find it from other manufacturers besides Rosebrand- you might be able to price shop. But if you buy from a roofing contractor make sure you
purchase the 600 series, it's the easiest to work with.
Jaxsan also isn't a great thing to being going down the drain (and is a pain to
wash out anyways) so make sure you apply it with brushes you can toss or trowls you can wipe clean before rinsing.
As for Crystal
Gel, I've never used it.
You could also thin Joint Compound with water or paint, but it's more prone to chipping by itself which I'm guessing is why
VSSSD mixes it with things like caulk and paint.