Lowner wrote in post #16172370
Dirty sensors can affect any DSLR, from any manufacturer.
As I've well found out with two 6Ds. Returned the first one, then decided I'd just accept it on the second. I wouldn't let the dust/oil issue be the sole factor in pushing you toward the 6D, because it can have the exact same issue.
Personally, dust aside, I'd choose the D600 if I could afford good lenses for it. The DR at low ISO straight up embarrasses any Canon SLR on the market; frustrating as it is for me, I can only imagine what it'd be like for you after actually owning a D600 and getting used to it. On the flip side, the 6D is slightly better at high ISO, and can push into the ISO 10000-12800 range with somewhat usable results.
Really, I think the D600 is the better all-around camera; it has better AF for action and sports, and better low ISO DR for landscapes. This pretty much leaves night photography as the one niche I can think of where the 6D excels.
But lenses are the caveat. Nikon is less forgiving of FF users on a budget, failing to offer affordable, slow lenses without IS (17-40L, 70-200L f4) for those of us so inclined. Seems like the only good UWA option they make is the 14-24; and while it's really good, it's also 2 grand.