I appreciated the test drive of the new version, but I have to admit that I don't really see additional features that I would use or need. From my view, it seems that many brewing software packages have pretty much what I need in them...pick lists with grain and hops, the ability to amend those lists and items, performs all the gravity, color, and bittering calcs, and allows me to save the recipe files for future reference.
I can see why the ProMash author hasn't done much on that program, it has everything you need. The only real change would be in the user interface. For the BS v1.4 users, I'm not sure that I see an appreciable reason to upgrade. v 1.4 is pretty good already.