I can't speak for casting large items in latex, but I can tell you my experience with latex is with molding over existing pieces. I used several thin layers so it would dry well, and that turned out well. Latex is something I think is easy for almost anyone to use, depending on your project. I think you'll like your end result in latex.
I hope I will get a good result from the cast. It will have a framework of fibreglass to keep its shape. It's just getting a model I am happy to take a cast from but am working on it
