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

I haven't checked my old camera yet but the first thing I did with my D600 was shoot a white wall and check for spots at a max aperature.  Yep, 2 spots. However it's really a stupid test since in regular shots it's a non-issue.  If it gets worse I'll get it cleaned.  Not a big deal.  Use the camera and go on with life.  If you get a spot or two on a picture you can clone it out in about 2 seconds.