The SLR Magic 8mm f/4 is an exciting lens for m43 that is optimal around f5.6-8. The above review is primarily video, but gives a good idea of the lenses distortion characteristics. For some reason there is some wobble in the video when he holds the Panasonic G85 above his head.
SLR Magic 8mm f/4: B&H Photo
Panasonic G85: Amazon/B&H Photo/Adoroma