There has been a sort of love hate reaction toward the 6D. I feel that the 6D is the perfect complimentary camera to the 5Dmkiii. Many pro photographers need a second camera, and I believe the 6D is perfect if you use the 5Dm3 as your primary camera. Almost every feature is complimentary. The 5D lacks the fancy connectivity/gps capabilities not to mention the remote EOS software for your phone, the low light focusing ability. The 6D lacks superior focusing, video ability and a few others. All while maintaining similar IQ. I have not heard this discussed. If you own both, you have almost all you bases covered with duplication of the most important qualities. If only the 6D could be had for 1500$ or less - maybe in a few months, the ebay offers will appear.