I have a number of polishers: Rupes, Flex, Makita, Walter, Porter Cable and several pneumatic polishers as well. The Rupes Duetto is the one I go to for finish sanding, it covers the acreage quickly, is light and easy to operate for extended sessions. It is well balanced and does not wear you out at all. Vibration is very slight compared to other brands I have worked with. The soft start is a must to prevent the machine from taking too much at startup.