Advanced legacy lens user: What to choose Olympus OM-D E-M5 or Sony NEX-6?

There's also the consideration that, while the body may be sealed, the legacy lenses almost always won't be.

Re: IBIS, I think it and OSS both get overrated, at least for stills. The reason I say this is that they only really help with static subjects, or people staying quite still. Even people sitting at a dinner table talking are likely to be moving too much for good shots at 1/10th of a second with a "normal" lens. If you're into shooting architecture and landscapes at night, hand held (as I am), then stabilization is great. If you think it's going to help you with sports photography or people shots in dim areas, you're likely to be disappointed.

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Nex-7 with kit lenses, Contax G 35, and a number of legacy lenses (mostly Canon FD)