OK so I was able to test out both bodies with the same lens to see just how much more fine detail the 5D had vs. the 50D. Here are my results.

The 50mm f/1.4 was used. The 50D image was taken at f/5.6, and the 5D image was taken at f/10. I backed up with the 50D to get the same FOV.

Both images were converted from RAW using DPP. NO NR was used within DPP for either shot.   Both images are crops for the full-sized image.. no re-sizing was done.

50d is the left, 5d on the right

ORIGINAL IMAGE

CROP 1

CROP 2

CROP 3