7D + 100-400mm IS L or 5Dii + 100-400mm IS L

2 Combo:
1. 7D + 100-400mm IS L
2. 5Dii + 100-400mm IS L

What is better

Thanks !

What do you prefer to usually shoot?

Both !

I meant subject wise...

You haven't provided what type of photography you are interested in so I will just guess. If you are buying a 400mm lens, I suspect you are shooting birds, wildlife, planes or such. With that in mind, I would recommend the 7D as it will have more "reach". As for the purist they will call foul using that term, but you all know what I mean. It will seem equivalent to a 640mm lens on on a 5d mark ii (on the long end).

When you include a 400mm zoom then the reach of a crop 7D and it's superior AF for wildlife or anything in motion makes it the better setup.

Forget the crop, the pixel density makes the 7D a better camera for 'reach' when used with a telephoto lens.

For example, if you shoot the full moon with the 100-400 lens at 400mm, the 7D will give you a moon that is about 830 pixels wide.. The 5D will only provide a 500 pixel wide image. The extra 300 odd pixels are significant.. It's roughly a 60% increase in resolution.

While you may not fancy shooting the moon, the same effect applies to other things, you may want to photograph, like aircraft at an air show, a duck in a pond or a bear in the woods....

Many thanks to all !