Upload & Sell: Off
I used a 1D Mark III and a 7D together for a short time. When I got the 1D Mark IV, I chose to sell the 1D Mark III and keep the 7D because I felt that the 1D Mark IV and 7D each had strengths that complement each other well.
While the 1D Mark IV is the best all-around body that I've used, the 7D is, by far, the best body that I've used in focal length-limited situations. I know that there are many who are down on the 7D, but I truly believe that the negative feelings toward the camera come either as a result of judging noise in an invalid manner and/or not being willing to accept the concept that, with a high pixel density 1.6 crop sensor, it becomes critical to keep your shutter speeds up at a higher level than with other cameras if you want to be able to get consistently good results.
There is another recent 7D/1D Mark III thread that is worth reading. If you read some of my posts in that thread, you will find more details about my feelings with regard to using the 7D successfully in focal length-limited situations, and I won't take the time to repeat them all here. In my posts in that thread, I did provide sample photos. Note that those sample photos were not ones that I cherry picked from the best shots I've taken with the 7D over a 3 year period. They were ones that I just happen to have taken earlier in the same day that I posted in that thread.
For me, when I'm not in a focal length-limited situation, I will choose to use the 1D Mark IV, but, when I am in a focal length limited situation, I reach for the 7D without hesitation. I've been working for 5 1/2 months on a project documenting an eagle nest. I've visited and photographed the nest and birds virtually every day during that time. While the single chick was in the nest, I used my 1D Mark IV and 500/4 from a tripod. Since the chick fledged, I've been able to follow it, observe it, and photograph it. To do so, I've needed a more compact and mobile rig, and I switched to using the 7D and my 400 DO (which is another piece of equipment that those with "internet wisdom" love to bash). The combination has been a joy to use. The 7D AF has not let me down a single time, even when shooting bursts of fast action with busy backgrounds, and, if I didn't know which camera/lens I had been using, I wouldn't be able to tell the 7D/400 DO pictures from the 1D Mark IV/500/4 pictures.
You can find those nest pictures on my website.
Again the shots of the young bird once it left the nest are the ones taken with the 7D/400 DO. Note that, since my purpose for the project is documentation, I do have some shots that I included which were taken under extreme conditions, including some that were totally back lit or extreme crops because I wanted shots of a particular behavior, but most of the shots do have better quality.
The bottom line is that, on a daily basis, I can come home with shots from the 7D that I could not have gotten with the 1D Mark III (or, for that matter, the 1D Mark IV) because, if I had to crop the 1D Mark III shots down to the same field of view as I get with the 7D, I would be down to about 6 1/2 MP.