While not scientific i agree it’s an awful long wait!
If i’m honest i wouldn’t run Vista on anything less than 1Gb of RAM
In my experience Acer hardware (desktops and PCs) have never had enough memory in their “base” configuration
We have a customer who aquired 20 Acer desktops (before we were looking after them!) that was running XP Pro on 256Mb
Once you have your OS up and running, some anti-virus/anti-spyware, Outlook, Word and IE plus whatever else open(reasonably typical usage?) that 256Mb doesn’t go very far