There are some pretty good detective tools on this page that might help you:
http://www.dnsstuff.com/
ie: see how many domains the server hosts, whether or not if it's on any abuse lists, etc etc .
Also,
I'd be interested in how you guys (and gals) would feel and treat affiliate webmasters that had their own domains on their own virtual web hosting account with a well known reputable host but their bill was being paid for by the sponsor.