No, I have not yet. The highest ISO I have tried is 640 which I found to be very clean. I hope to try high ISOs soon and will let you know.Antonio, have you had a chance to take some low light photos with the M9? I tried to take some photos at a darkly lit bar on Friday with my M8 but there was quite a lot of noise. I'm thinking of getting an M9 but am afraid ISO performance is only marginally better.