I'm a heavy Canon user - I've upgraded from a Rebel XT to a 40D and 5DMKII. I bought my wife an EOS M3 a few years ago and have been very happy with its performance - I just needed a bit of speed to match the central focus of my 5D II. That's it. I lose the full screen style but gain a lot of nice features by using it instead of the 5D in my bag. And with the 22mm f/2 kit, I'm consistently impressed with the image quality. I don't like some of the other EFS-M lenses that much, but I carry an adapter in my bag with my regular EF lenses and I love it. The mic is a huge upgrade over the built-in mics (which are good in a pinch) and I'm impressed with the video quality I'm seeing.
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