I think you are possibly mixing up two products, type H paper = "canvas" base (available in matt and glossy), the "velvet" paper is a different paper again it seems... Anyway, I think such speciality papers are really difficult to describe and given the considerable investment for a roll of these papers I would definitely ask the supplier for samples to see if it fits your needs. The supplier should also be able to tell you how the contrast and saturation behaves in relation to standard CA and CA DPII. Unfortunately I have used neither of the two (canvas/velvet), so I cannot contribute anything further.