so theres no need to make a calibration to the ACDs is that what u mean?
No I would not say that as a general statement.
I would suggest this: If you are a graphic artist, to whom a colorsync color matching system is important, then the ACD provides a complete out-of-the-box solution that integrates with ICC profiles from scanners, operating systems, desktop and wide format printers, Offset and Web Presses, other monitors and cameras.
However, one can do quite well by buying a more-affordable non-apple monitor with a calibrator -- this former solution can actually be more useful to this said designer. However, it is important to:
1) Buy a calibrator with software that can generate "portable" ICC profiles -- this is important so that one can "Share" the profiles with clients as they send files with this profile embedded.
2) Learn how to use the above software.
3) Buy a monitor with an S-IPS panel as the color tables are more stable and suited to desktop publishing as opposed to video or games.
If one does not wish to have the trouble of the above, or to spend the money on the calibrator (often offset by lower monitor cost however), then the ACD's are a great choice for DTP work.
My 2 cents,
Dante