I went from the D200 to D7000 for better low light capability and the camera has been a good performer. I'm waiting until this fall to see what a possible D400 will be and then expect to upgrade bodies. I was originally thinking a D400 with perhaps a D600 backup, but after using the D800 for 10 days recently, I may switch my thinking. The D800 is a stellar performer and I could be very happy with it. A lighter DX body would then become the backup/travel alternate.