From a pricing standpoint I have found Rackspace to be more flexible at the lower end 256MB slice but once you start going higher toward 1.5GB RAM it gets more

From a pricing standpoint I have found Rackspace to be more flexible at the lower end 256MB slice but once you start going higher toward 1.5GB RAM it gets more pricier than Amazon. I am guessing you were referring to RackSpace Cloud. The pure Rackspace solution is very pricy compared to AWS.