I have been considering this same problem. The key to remember is that with watercolors you leave the white of the paper as your white and gradually build up your darks. Whereas, with acrylics (and oils) you put your darks down first and add lighter and lighter colors finishing it off with white as your...
I want to explore using acrylic on my watercolor paintings. Anyone out there doing this already? If so, what paper are you using? I just bought the fairly new Strathmore Mixed Media paper to try.