This review is based on our usage of Rackspace Cloud Servers for more than 5 months (September 2009 to March 2010).
Rackspace Cloud server would be the best option specially for small or even big companies who dont have a lot of heavy bandwidht usage, like downloads, Video viewings etc. I have used this servers for a no. of puposes. So let me review them.
As a replacement of Dedicated Server (4.5 Stars)
I believe it is one of the best replacement for Dedicated server since it is very flexiable. You can upgrade and downgrade anytime. You have complete control. And the best part it you can add and increase as many servers as possible. Sometimes i created more than 3 servers in a day to do some testings. Deleted them when i was done with it.
Costwise and Upgrading (5 Stars)
I believe it is one of the most cheapest in the industry.
Only dollars 10/month for a 256MB server. And you can upgrade anytime without any cost. You are charges only for the time the server in created. Charges are hour based. If you create a server for only 3 hours you are charges in cents!!!
Installation and Working (5 Stars)
Though they dont provide any help on installations they have a wonderfull wiki available for you. A very good wiki, using which even an novice, who has never (never means never) touched linux can Install the complete LAMP. And get the server into running. The wiki provides help for installing Linux, Apache, MySql, Control Panels, Mail Servers, Firewalls and what not.
Customer support (4 Stars)
Actually we all know the Rackspace is famous for its customer support, but to tell you the truth I have had some bad experiences with them. Once there was a problem from their side. (I had hosted one of my site on their cloud sites and later deleted that account and shifted it to cloud servers. This caused a DNS/Duplicate domain problem from their side as they has not deleted my complete information. And I was not able to get my server working for more than 2 days inspite to repeatedly informing them.)