Originally Posted by
dipstik
I've had a similar realization recently, and have been contemplating selling off my 5D and 40D in favor of a MkIII.
My issue is that the 40D has not been much better at shooting action than the 5D. I thought the 6.5fps would have changed my shooting, but in reality the 40D has the same (or very similar) AF system as the 5D: 9 points of AF, but really only the center point is reliable for tracking action, which awkwardly limits how you compose the image if you are trying to shoot tight.
I've realized that when you are tracking a moving subject, it doesn't matter how many FPS the camera can fire off UNLESS it can maintain focus throughout each frame, and the 40D has disappointed me in that regard.
That being said, the 40D is useful in that it turns my 70-200 into an effective 100-300 f/2.8 zoom. Slap the 24-70 on the 5D, and you are good to go for just about anything, so long as it's not raining...