I used a low-key image of a model posing in front of a dark background with a black feather boa at her feet. The three papers were
--Epson Ultra Premium Photo Paper Glossy 79lb.
--Kirkland Professional Glossy Inkjet Photo Paper 69lb.
--Red River Ultra Pro Gloss 68lb.
All three prints were made on an Epson Artisan 50 with Claria Inks with the printer set to control color and the setting at Epson Ultra Premium Photo Paper Glossy (as recommended by all three manufacturers). All were printed from the PSE9 Editor.
Results: I could not visualize any difference in the printed images, however, the Red River paper feels slightly stiffer and heavier than the others despite being the lowest of the three in lbs.
Red River markets a number of additonal papers that I intend to try, and report on, either later today or tomorrow.