Hi swizz
Well how i make my print jobs, i uses both CMYK and RGB color mode in the same file.
first I create a file with RGB color mode becauze it allows me to use all filters of photoshop. when i make sure that now i dont want to use any filter or third party plugins, then i convert my file into CMYK and then finaly i adjust colors of my file with level or color balance, if needed.

I hope i asnwer the question.http://www.talkgraphics.com/images/smilies/smile.gif

Regards
Shiraz