"Don't forget to add your reasons too!"
But don't forget to add the scope of the project either. With no scope, I'm sticking with Rackspace. Their phone support is a must when crap hits the fan, it's 2am and you have no idea why something isn't working. And they will answer; generally within 2 or 3 rings; and you get a tech, not a low level customer support specialist. (personal experience that has happened)