I had typed about 40 lines of reply, and when I hit post the message dissapperd. I got dumped to the forums page. The gist was DLSR have many advantages over Prosumer cameras. I will retype my tips on keeping dust of the sensor. 1) Power the camera off when changing lens. With the power on the sensor is a powerful dust magnet. 2) Hold the camera with the lens pointing down, when changing lens. More chance of dust falling down to the ground than on the sensor. 3) Try to change lens in a clean environment. (No really practical, but if you know you are going to shot wild life then put on the big telephoto lens before you leave home.) Now hopefully at least this will post.