I have a D80 that I love. Now that I'm thinking more seriously about photography, I'm wondering if I should upgrade to the more flexible D600? (I know there are a lot of enthusiasts for the D7000 but apparently FX is de rigueur.) Or should I keep the D80 and spend my money on high quality lenses? I have a 35mm 1.8 (which I can't use on an FX camera), the 18-70mm 3.5-4.5 kit lens, and 70-300mm 3.5-5.6 VR. I shoot landscapes for the most part so I don't need speed as much as sharpness. Any input is appreciated.