After intensive use for a month, both outside in good conditions lumiƩres than inside during the holidays the night, I can tell you that the picture quality is exceptional.
In video mode the quality is very good, smooth HD video, you can not hear the engine sound that is super discreet. I can easily zoom while recording, it makes the development quite quickly.
FYI I use it with a Sony Alpha A77, and I shoot in RAW mode.