Sadly, it's not all good news with this lens, as we ran into a very odd, and repeatable, issue with this lens relating to motion blur caused by the shutter actuation at certain shutter speeds. Despite testing the lens with IS turned off and on a ~250 lb. studio tripod, we observed noticeable motion blurring at slower shutter speeds at the longer focal lengths.
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We first encountered this shutter-related blur issue way back with the original Olympus E-P1; we posted a very detailed analysis of the cause as part of our Olympus E-P1 review, in September of 2009. Depending on the particular lens and body in question, we've seen the same problem (albeit generally to a much lesser extent) on pretty much every Micro Four Thirds camera since then...