I have the D7100 and am very happy with it. That being said, if I, like you, were planning to go FF in the next year or two, I would buy the D600 right now. A friend of mine has a D600 and we have compared quite a few shots between that camera and my D7100. In good light, they look very similar, but if you need the FF wide angle and low light performance, go with the D600. By the way, my friend's D600 has had no sensor garbage problems in the 3-4 months he has had it.