> Printing an 8x10 from a cellphone is challenging, and the grain and imperfections are magnified.

Have you verified this personally or seen any data on this? I find this claim very hard to believe. I make several 24x36 prints in a year (albeit from APS-C and FF sensors, but sometimes heavily cropped) and 8x10 is a tiny size that should not present a challenge for any modern cellphone's sensor.