Quote Originally Posted by Anbesol
"It gets you closer and you'll have more depth-of-field with the same angle-of-view. That means it's easier to keep the whole product sharp. And that's one of the hardest things to do with close-up work."

Well, sort of, only by bringing it through the sweet spot of the lens, but this only differs by and between lens', not the bodies, if he got a solid EF macro lens I can't imagine that would be a problem. You could also crop the image from 5D and still get the same effect of the APS sensor.
Just cropping the image won't give you the same effect! You have to realize that the spacing, pixel pitch, size, and depth of field depending on physical sensor size. For "part" photography, you're going to want the deeper depth of field of a crop sensor.