I've used my Panasonic 20mm f1.7 on the OMD and have yet to try the Pana 14/45mm and my 2 legacy lenses from the film days of 1980 onwards, the Canon FD 50mm 1.8 and 35mm 3.5.
I still like my GF1 a lot as it's a workhorse and I feel the settings are easier to navigate.If it had an EVF , I may never have got an OMD.