I used to have the olympus 14-35mm f/2 for 4/3.
An amazingly sharp lens even wide open.
'Yeah! But a great looking ship though. Looks like a fish, moves like a fish, steers like a cow.'
The AF was slow and jittery - and manual focus was impossible on the tiny 4/3 viewfinder ( and the E-3 was the best 4/3 viewfinder ).
Donald.