Originally posted by Imp
And you have to manual focus with that combination? I'm remain interested by the concept of m43 for wildlife, so I like to hear about people's experiences

My technique in a nutshell:
Multiple cameras on tripods prefocused where I anticipate the birds will fly and fired remotely. I have about a 1% keeper rate (alot of out of focus shots, tack sharp is rare).
Depth of field - a constant for frozen motion for backyard birds is ambient light shooting at shutter speeds 1/1600 (Blue Jay sized bird) to 1/2000 (Titmouse sized birds). This of course directly affects ISO and aperture. The gift and the curse becomes a decision between how clean do you want your image in regards to noise (ISO) and how deep of focus do you want. Depending on the available light (I shoot all weather conditions to maintain unique shots) I may be forced to shoot at F2.8 or faster. This helps remedy high ISO, but an image may not always have the entire bird in focus.
My advice - when shooting this technique is capture first and all other technical photography steps second. Equipment and skill is still needed, but if I cant get in position to take the shot I wont have an image to talk about. I'm doing more hunting than photography.