QUOTE(gogo2 @ Nov 26 2009, 09:20 AM)
got big different until u wanna sell ur oly? how much u get 20mm?

Added on November 26, 2009, 9:21 ambefore you sell, can do testing for us?
Shoot something using both lens and do comparison in terms of sharpness, speed, bokehness etc..
Probably you can try to use f/1.7 and f/2.8...

The Pana 20mm & Oly 17mm are both great lenses.
After testing both, I decided to fork my $$$ on the Pana 20mm.
here are my analysis:
Pros for Pana 20mm
- at f1.7 its about 1 stop faster. That's important when you want to shoot in low-light esp. street photography
- at all focal length its sharper, especially at edges and corner
- I seems to like the bokeh better eventhough both bokeh performance are good but not stellar.
Pros for Oly 17mm
- slightly lighter and smaller
- silver color matches nicely with a silver PEN! :-)
- Better control on vignette
Bottom line is, I enjoy using both lenses but one have to go! :-)