Only D600 has the dust/oil issue or its regular about Nikon cameras?

Can I say that I was a self proclaimed nikon know it all because I thought I was all set until I hit 2,800 shutter counts. At that point I noticed spots in my shots at even f4.5. I would say anyone that thinks they are safe should wait a year or until over 10,000 frames before you start thinking you are immune from this issue. This is not a made up think. My gallery shows the fun oil issue. I think if the lubricant was consistant we would all have similar results but since some cameras are lubricated more or less that would explain the variances. Either way lets not say we should not have an issue. I should not have a clean sensor at 12pm and oil at midnight at the start of a time lapse test.