I've used several boxes of 11x14 and a good share of 16x20. I have tried it last week with hybrid negs with great results as well, but I do prefer the optical negatives as they really are better quality prints. (that has nothing to do with the paper,btw, but the neg itself, of course)
I would like to see some larger boxes of 20x24 and maybe even rolls. (at present, I don't know if they are available)
Truly one of the coolest products on the analog market. I would love love love to see some other papers like this come to market, like Arches Platine. mmmmm
Great stuff all around.