I have this camera since march 2017. The QHY16200 has been a pleasure to work with, but there is 1 strange problem with it. After about 6 months of use a grease like trace was beginning to appear on the bottom-right of my images and flats. At first i could not remove it from the sensor glass with the Eclipse sensor cleaning fluid, but after I got the Smear Away I was able to remove the grease trail. But after a few weeks.... the smear creeps back into view, etc.
I have the camera switched on 24/7 and the sensor is cooled to -20C, but only during image sessions. Are there other users that have the same issue?