Mine arrived from B&H on Friday and yesterday (Saturday) we had a beautiful near-record spring-like day! Nearly 70 degrees F in NE Ohio in February!
So I took my new 100-300 II out to the local Duck Pond. I would say optically it is very similar to the old one (which I was satisfied with for what it is) but the AF and shutter blade response is dramatically improved. I'm looking forward to trying it out in the fall at our local air show where the old one was just too slow to keep up.
The only thing missing that I would have liked is a focus limiter. But I haven't had any focus hunting issues so far.
Below are a few (mostly wide-open) test shots from home and then shots from the duck pond.
All shots handheld, EM5II, from Raw processed normally in LR. Full Size Images via the link to my Smugmug site.
I was trying both the lens' PowerIS and the EM5II's body IS and don't remember which one was used for each shot. With Panny lenses on Oly bodies, you have to pick one or the other. There is no "Sync Is" or "Dual IS" possible. No opinion yet on which may be better.
The same nice close focusing at 300mm as the old one:
300mm, 1/25, f/5.6, ISO500
286mm, 1/320, f/5.6, ISO200
286mm, 1/200, f/5.6, ISO200
300mm, 1/250, f/5.6, ISO200
300mm, 1/640, f/5.6, ISO200
171mm, 1/800, f/4.7, ISO200
100mm, 1/800, f/5.6, ISO200
100mm, 1/1250, f/4.5, ISO200
300mm, 1/640, f/5.6, ISO200
300mm, 1/400, f/7.1, ISO200
--Mark--