Summary: I bought this D600 from a guy who bought it factory refurbished from Nikon. Apparently, he shot off about 2,200 pics without any hint of the notorious dust spots issue. Nevertheless, he sent the camera back to Nikon to have the shutter replaced before putting it for sale on Ebay.
Summary: The dust issue continues to reoccur OVER and OVER. Local camera shop will clean sensor for $90. EACH TIME this happens I need to fork over $90??? And it happens frequently. Every 1000 shots or so.
Summary: I purchased the D600 body about a month ago. I had used all my savings that I have been saving for about 2 years. I was very excited to buy a full frame camera after having used D3000 for about 5 years of my life.
Summary: This is a long post. The quick synopsis is as follows: The D600 HAS an issue with dust and oil. They have admitted to an issue finally in Feb. Their cust service is the worst I have experienced. After 6 months we got a full credit from the vendor and purchased a Canon 6D.
Summary: I purchased this camera to travel to South America. I had used a D7000 for a year and I have 4 other Nikon SLR bodies. Two days into the trip spots started showing up. These are not dust spots since you can see them when the mirror is locked up and they appear as small smudges on the sensor.
Summary: I was a first adopter and bought my d600 in September 2012. I like to shoot long exposure which accentuates a dirty sensor After a month I finally noticed spots/oil and sent the camera to Nikon for repair and in a week they returned the camera.
Summary: I am a newspaper photographer and have had Nikon D200s, D300s, a D700 and (for my own personal use) a D800, and have been very happy with these cameras. I take good care of them and have them cleaned regularly by Nikon Factory Service (In my opinion, don't go anywhere else for service).
Dust/oil problems - DO NOT BUY until Nikon fixes the issue
B. K., Amazon
24 February 2013
Summary: Nikon has finally admitted to the well-documented problems with spots on the D600 sensor. Look at sites like dpreview, lens rentals, and the reviews here and you will see this is a real and serious problem.
Summary: Had my D600 for a couple months and didn't notice too much of a problem. We were into over 5000 photos when dust spots suddenly went from mild to severe over the period of about 4 hours ..... during a product photo shoot.