my buddy shoots with a d600 and d4 they are great cameras but when looking at the photos he takes vs the photos i take using my d3200 or my trusted old d700 the definition is comparable, not saying they match but to the lamen it would hard to to say which is which. the camera is only as good as the glass in front of it if your using kit lens with fx camera your still not getting the full potential of the camera. he shoots freelance for Gainesville sun and the alligator, mostly sports and his D4 is just a mega machine when it comes to sports shots. you should check out some of his work http://www.brettleblanc.com. most of his shots were using the D4 on there.