I downloaded build 5456 yesterday and I have been having issues getting this build to install correctly. What is odd is that I am using a system that has been running previous Vista build without much problem. I don't remember the last build outside of 5270 that installed smoothly, which has me a bit concerned.
It seems that the install process gives you very little information about where potential conflicts exist in either your hardware or even the lack of drivers within the native OS. There appears to be a LOT of room for improvement to getting Vista to install on hardware. The most frustrating part for me is that I need this stuff to run to work on my lab configurations for testing the network performance. Go figure eh?