I am using SiteGround.com Drupal Hosting right now, and though a lot of people don't like it, I haven't had any problems yet.
I am going to be creating 4 domains that point to one instance of drupal (preferably 6.x). I've seen bad reviews of SiteGround, and Site5, and some positive reviews of: ANHosting, HostGator, MidPhase, BlueHost I was looking at ANHosting since I saw one bad review, and mostly good reviews.
I don't need a full VPS dedicated server .... just the Drupal hosting preferably with a good support and good database servers.
Thanks! Tom