I have a customer who swears by Compuhost. I have been working with him for the last couple of months with the same Vista issues that Hoster is having. Sometimes, for no readily apparent reason, Vista just looses sync with the video. I pinned it down to the audio drivers for Vista. There is a memory leak, but only on one computer. The same card and driver on another computer doesen't have the same issue. We had to change brands to a different card. Actually it was an inferior card, but the drivers workd better in Vista on this particular machine. They even have the same kind of suggestions about resources on their sales pages that we have here.
http://www.kjtools.com/chsystemoptimizing.html is just a taste of what I found in their forums. They have the same complaints, and usually the same fixes, that are posted here.
This alone should tell you that Hoster is not alone in problems with other programs and services especially when it comes to Vista. As long as a reasonably competent person is willing to make the changes, you should have a trouble free show machine. I have ran Hoster on a number of different computers with no serious problems at all. I tried to help you out a while back to tell you how to eliminate the resouce hogging issues with Vista. If you have a competent IT person, refer them here
http://www.blackviper.com/ this will get your systems where they need to be to run a profesional show.