I've been using semi-matte (Arista.EDU RC #2), but that's for pinhole work, so I doubt I could tell whether the surface affects anything. I bought it because it's my preferred surface for prints, in case I gave up on paper negatives. I'm about to try some 8x10 contact prints from last Sunday's WPPD exercise, but I can see the whole business is at best a work in process here!