Ok well i was lucky enough to find someone wanting more reach than the 5d could offer. So we traded my 40d with a sigma 18-50 Macro 2.8 for his 5d body. My impressions. Build: 40d and 5d are on par, however i would give the build to the 40d, I dunno why but it feels more substantial in my hands. Everything feels just a little bit tighter on the 40d. But the 5d def feels ahead of my old 30d back up. IQ: Well there isnt much to say, we all know the 5d images seem quite different than the 40d. Just better. Maybe its the depth you see. Or the better looking OOF areas, i dunno, just something abotu it is better. Not to mention teh lower noise, and the better white balance. AF: I hate to say it but the 40d is miles ahead of the 5d when it comes to focusing, i didnt think i would notice much of a difference but man, its true the digic 3 and the cross sensors do magic. The way the 40d locks on to focus is sooo much faster. When i point at something It snaps to it. the 5d is a bit slower. even with the 85 1.8, its substatially faster with the 40d than it is with the 5d. AF is notably slower on every AF point other than the center. Its the name of the game, thank god i have my 1dmkiiN for the fast moving stuff. All in all, if i didnt need the extra Noise performance, and the DOF of the 5d, i would still have the 40d. Definately without saying the 40d is a much more well rounded camera. But if Picture quality is your only concern the 5d is for you.