I’ve been successful using acrylic paper. It’s much cheaper and great for experimenting. Sam I think you asked about this. I mount it on a board with tape then apply 1 or 2 gesso Coates to seal it. I tone the gesso so I can see I’m it applying uniformly. Use a very soft brush to smooth the surface Then it’s ready for painting. Before each gesso I mist the paper and smooth out the water film. When wet sometimes it does buckle but when it completely dries it goes back flat. Note that the tape can stick and tear the paper when removing. I use a hair drier to soften the tape before pulling off. Kind of like you do in watercolor. I’ve found a big difference in paper thickness and quality. A photo of the type I use. I tried canvas paper, but it was lacking. Never tried painting directly on the paper, perhaps it would work.