No, you don’t. As far as I can see the advantage being you don’t get dust on your sensor when changing lenses as it’s a sealed unit. But the prices aren’t too bad…comparative to Leica as Ricoh seem to be subtly trying to emulate.
Quite interesting, but… Very expensive. As a matter of fact, only macro module seems to be really interesting thanks to APS-C sensor. The 24-70 (S10 module) utilizes 1/1.7 sensor which is rubbish. That is weird.
This stuff is not a competition for micro 4/3.
It is nice to keep the sensor clean, but it makes the whole play too expensive. I see no future for this system.
The ultra-sound shaking is much cheaper and very efficient.
This was a theory deployed during the early days of PCs – a “shell” PC which could be upgraded easily when technology advanced. The problem was that the technology did not change in discrete units – e.g. when teh main processing chip upgraded, there was also teh need to upgrade other circuitry. So teh upgrade path was quite short.