Unless you plan on shooting with both bodies simultaniously it doesn't make much sense. As stated above, every new genreation of bodies has significantly outperformend the previous genration. In 5-7 years the D700 will be at least two and likely three or more genreations old. In addition, the price of camera bodies seems to drop every time a new generation of bodies is introduced. It would be more cost effective to have the shutter on your current D700 replaced if and when it fails. Good Luck and Enjoy your Nikons!