Sun's EC2 Support sucks
So I’m pretty disappointed in Sun. I’ve made good things happen with OpenSolaris and EC2 separately and I was pretty excited about using them together. But we’ve been waiting for three weeks for a reply to my inquiry regarding OpenSolaris I/O performance in Amazon EC2. I can only assume there’s an issue that they’re not ready to talk about because they were very responsive to other questions. This is an unwelcome contrast to the type of support we’re enjoying from Amazon.
My advice: Stick with Linux on EC2.