I totally agree with the fourth comment here, and absolutely disagree with the second post. I was at one time obsessed with photography and image quality, so I bought a Canon 350D back in that time, and last year a D5200. Needless to say they provided fantastic photos, 350D was brilliant at that era, same goes for D5200. But then I lost interest in photography for my business and sold both of them. Another definite reason for selling them was their bulkiness, oh man, I am just a skinny guy of 64 kilo and those thing were heavy. I always believed that the camera you will be using more is the camera you want, with the D5200 I just knew I had a great camera but as soon as I looked at it it was like oh God, no I ain't carrying that.
Now about picture quality, I think some people have not used Micro four thirds here but they do comment about them! I don't know about the 3N, but I have used my friend's F3 and it was fantastic, I took lots of shots at night of his wedding and they all came brilliant. Were they as close as D5200? No, but with slight editing they were somewhat comparable. You can go for higher range NEX, maybe they are better, but I am not sure.
And I absolutely am against the RX series here, they are extremely overpriced for their purpose IMHO. Whatever jibber jabber technology it uses it's still a tiny sensor! I will never pay 15k if not less for a P&S. And no, for low light it can never provide shots like NEX series!