I have very little experience with EC2 (or managing server farms). I have worked at Amazon and been responsible for an internal service there that ran on a ser

I have very little experience with EC2 (or managing server farms). I have worked at Amazon and been responsible for an internal service there that ran on a server farm, but we didn't use EC2 and another department managed the machines. Has EC2 been reliable enough lately? I've heard horror stories of 8+ hour downtime multiple times a year.