I take it you don't have PDF workflows and you are still resolving .ps and Oppo files?
Otherwise, why would you want to print out a files (.ps) and lose all of the .pdf functionality that you get with a PDF workflow?
As others have stated, you can utilize shared printers on a mac running an older OS.
Personally, I like shuttle. The XML settings available though shuttle make setting variable options (seperations, distortion, screening etc.) very user friendly.
I will say that an Indesign shuttle plugin would be nice!