The only metallic I have tried on the 9900, is the Breathing Color Vibrance Metallic. This is RC based.
Very nice look to the prints, however the substrate of the surface seems to trap fine dust particles into the print. They show up worse in large dark areas. Tried a few different things i.e. slowed down passes, etc. but still get them.
So that paper is not a good solution for your 30 x 40. The only other metallic I am considering right now is the Moab slick rock, waiting on a sample pack.
Paul C.