They didn't hit any of my pain points.<p>The payment schemes weren't particularly complex/annoying. What is annoying is that when you purchase a RI you cannot just point at an existing VM and have the RI both bind to that but also select the right availability zone and location (e.g. 1A, 1B, 1C, 1D, East, West, Central, Europe, etc). I've had to go through the painful process of migration from 1B to 1C because I mistakenly purchased US-East-1B instead of US-East-1C.<p>Plus there is something to be said for Azure's "you can always upgrade it" model. RIs are great price wise, but Amazon won't let me buy e.g. a small RI and then pay the difference to upgrade the RI to a medium or large (even if they have to extend the RI to do so).<p>This is really the most welcome change (NOT listed in the blog):<p>> On February 2nd 2015, Light and Medium Utilization Reserved Instances will no longer be available for purchase.<p>Light and medium RIs were too complicated. It was also too hard to track your RI usage in the way you'd need to to manage those plans, it is just easier to do on demand pricing with a few heavy utilisation RIs.