RC paper's won't work well in my experience the muck will not bond well to the RC paper backing.
With cotton papers, you need a thick paper 300 W is the best and you should make the coating on the board as thin as possible. You still need to press the mount, but it's a bit tricky since you don't want to mar the print, I place a cover sheet made from release paper on the face of the print.
Papers I have mounted, Canon Platine, Optica 1, Canson Arches, Epson Exhibition Fiber.
It's not as nice as a coated canvas as you still need something like glass to protect the face of the print, at least I did.
Paul