I recently made the plunge & got a used em-5, but am still very much the noob. I bought two lenses, 12 & 45, both Olympus. I was thinking about adding the Panny 25 or 20 at some point soon. Is there any concern with using this on the Olympus? I know they are designed to work together. But the systems focus differently, correct? In body vs. on lens? I read the thread about the Oly locking up, thinking that may have something to do with cross lens use, but it didn't appear to be so. So long question short: Can I use the Panasonic lenses on the Olympus without a problem or is there something I'm missing? Does it focus as quickly? Thanks, and if this has been covered extensively, my apologies.