I'm currently controlling several SageTV HD200s and SageTVClients (and a SageTV HD100) through Prontoscript over IP - basically http calls (retrieving video/audio/image database and requesting playback of said content).

One downside to the HD200s is that they won't pass or decode DTS-MA/True-HD. The BD Prime appears to decode HD audio streams and has 7.1 analog out (which is good for some of my old equipment)

Is the IP based control going to be available for the Dune Prime 3.0 sometime in the next few months?

I am not sure of the release date for including IP control in the BD firmware. My experience with it has been very good from a control standpoint. I believe they are working to provide more feedback regarding specific state rather than just completion status. Based on the way it operates it is completely possible to build a complete control system for the Dune Player using just a pronto. This could include a full librarian, although the total voluime of content might be too much for the pronto. My librarian runs as part of my Theater control system, is fully automated and displays on the main screen, as opposed to displaying on the Pronto