I've compared LR and Genuine Fractals 6 and Photozoom Pro 5 uprezzing a 16MP micro 4/3 image to print at 360 ppi (Epson native resolution for normal quality) on 17x22" paper with a little cropping. That's around a 180% uprez. GF and PZ were roughly equivalent, LR was inferior. You could see staircase artifacts on diagonals in the LR uprez that were not present in the GF and PZ uprez. That said, it's not something you would notice if you nose was more than a foot from the print. But the difference is there. Sorry, but I'm pretty sure I don't have the comparisons handy any more.