Thanks Holty - there's a thread full of those shots somewhere.
Image quality is great as long as the optics are good. I'm happy to use up to 3200 ISO outside and 6400 for indoor work like the above. Focusing seems unimpressive compared to a Sony SLT using a centre spot, with the camera struggling to focus in low light (say 1/90 f2 @ 6400ISO). All my lenses are older screw-drive types or manual focus, and I've no idea how it would cope with fast action focusing.
I like: Reasonable weigh for FX, nice to hold, 2 control wheels, AF defeat lever is easy to reach, great sensor performance, AF assist is handy.
I don't like: lens mount inferior to Sony/Minolta A (hard to line lens up right, easy to miss) spot metering seems to use the central 10% rather than 1%, single focus spot occupies too large an area, menus aren't great, doesn't feel better made than my entry-level Sony A58, sensor picks up dust very quickly, fixed rear screen is stupid, live view is awkward.
It's capable of producing great images and the sensor is excellent, but it's not a camera I would buy if I wanted to rely on the camera to take great pictures in difficult conditions.