I have a Panasonic 20mm on the way after much deliberation. The 1.7 aperture is what did it for me, plus the rave reviews about image quality.
The 17mm fov would be great (and the price!), but I'm used to much faster lenses from my DSLR experience.
You my friend are in for a shock.
The 20 is not what it's cracked up to be!
It's more! You will find as others, it's hard to take off the camera.
Enjoy, you made a great buy....
Would you still pay VAT if the lens was sent as a gift from me your cousin in the US?