Sandy, as for the versitility of agitation verses minimal or no agitation and PMK, I have a reference article that was written by our own Patrick Gainer in the Nov/Dec 2002 issue of PHOTO Techniques. PMK seemed acording to his testing proved to do very well with minimal and no agitation.
I personally have used both developers. I found no discermnable difference. I just prefer using the one I had a large stock of which is PMK. It's like you say, you go with what you know and feel comfortable with.