I also bought mine knowing about the dust issue. I got a refurb thinking Nikon may have fixed it and it is what I was lead to believe by the store's salesperson. Sadly, mine started exhibiting it after 70+ shots with it and pretty severe too. Thankfully, a blower was enough to clean 99% of the dust. I can certainly deal with usual cleanings if it only deals with a blower but if I have to wet clean every few weeks or even few months, I certainly would return it.
So far, no regrets! D600 takes wonderful shots and the pleasure of taking photos with it certainly outweighs the dust issue.