Have you seen that the Ghost Script pdf parser is actually written in PostScript? Generally we are looking to get rid of all Adobe fully, but purely due its pricing policy, not because it is bad software. So we have successfuly cut a lot of cost by this solution, which might be not for printing service. As for the commenting of PDF drawings PDF Xchange is for us even more pracital than Adobe Acrobat with much more options, presets of annotations etc, integration into Windows Shell. Proffesionall printshop etc is a different story. So for us PDF Xchange was a great solution.
Adobe Reader itself is useless except viweing th files, it cannot do almost anything, and to buy to 60 seat office of engineers an architect 60 licences of full Adobe Acrobat only for this purpose is just too expensive and unnecessary.
We were not looking for advanced color speration functions or advanced printing etc. The functionality we as architects need is mostly commenting drawings, combining booklets, rotating, printing, replying comments, distribution of documents. Of course it is qestion of purpose of software you are looking for.
