This is the best image viewer in the history of Apple Macintosh. It's got the best scaling/speed displaying features. Back in the day of 256 color performas, this app would take a 16-bit image and render it beautifully on a 256 color machine. Years passed, and the app was still amazingly usable. I used for viewing images in full screen, not slide show. It was way better than pictureviewer at scaling, performance and preference options. I really wish this jem makes it to carbon....