I'm trying to decide between the Oly 45mm f1.2 and the Panasonic 42.5mm f1.2 lenses and would like to know how many stops dual IS adds with the Panasonic on the G9. I've searched, but can't find anything. I called B&H and they told me that the lens IS would add 5 stops. I don't think that is right. Does anyone have this information?

Thanks,
Charles