I fill my own cartridges with quality ink and use Red River paper for the most part. I print 4 X 5.33s which is the right ratio for most non-SLR digital cameras. I can get 4 on a sheet for about 6c each. I prefer to print 5 X 7s to pass around and they are about 12c each.
You have to profile for non-factory ink and paper, but it is worth the effort. Canon Pro paper and Canon ink give ever so slightly better prints, but at a very large cost increase.