I am thinking of purchasing a D700, I know that probably next year would see an upgrade. But as it is now its already an excellent DSLR, do I need a probably higher pixel count, it is said that its a great low light performer. I wish to move up from Cropped sensor to obtain FF advantages. Can you please help me highlighting the advantages. I am interested in macro, portraits and stills. For use with 24-70 f/2.8, 105mm and 70-200mm f2.8. Thanks in advance.