I can't release the full results of the ones I've run, and they didn't cover Micro instances (this was about a week before they came out). I can say that when

I can't release the full results of the ones I've run, and they didn't cover Micro instances (this was about a week before they came out). I can say that when executing kcbench (set to do 4 kernel compiles, same configuration on all machines, using a '-j' equal to the number of CPUs in /proc/cpuinfo) I got the following times: EC2 Small Node: ~849 seconds Rackspace 1GB Node: ~81 seconds From what I've seen, a micro instance can supposedly (that is according to Amazon get more "burst" cycles than a small instance, but in the long term will be significantly slower. A sibling to this comment refers to some work that compared small nodes to micro nodes, and found the small node to be over 2 times faster than the micro node for large processing jobs. Based on that, for CPU heavy jobs I would put a 1GB Rackspace node at something like 25x faster than the EC2 micro node. I found that for the most part, in order to compete with Rackspace on CPU you needed to go with at least an Extra Large (which was about on par with Rackspace) or a High-CPU Extra Large (which managed kcbench in ~44 seconds).