My first FF DSLR was a Canon 5D. Great camera but also prone to dust spots ala the D600. If I got one that was noticeable I simply cloned it out during PPing. If the dust built up I cleaned the sensor. In the days before internal cleaning mechanisms this was considered par for the course. Self cleaning was the obvious response to the problem of sensor dust on an inter-changeable lens camera. My D600 has none of the aforementioned dust spot issues. My suggestion to anyone with visible dust on their sensor, no matter what camera you have, is to clean the sensor in the appropriate manner and get used to having to do it from time to time. Eventually I'll have to clean my D600's sensor, doesn't bother me.