If your work is about shooting moving subjects, I'd test again in those conditions.
My guess is that a D2x/1Ds2 in AF mode properlly used will deliver an image with more absolute detail than any MFDB used in AF/MF mode.
You migtht be able to do better from time to time with the MFDB from time to time, but think average image quality per hour of shooting.
Just my 2 cent.
Cheers,
Bernard
