How does ProsperOps deal with EC2 capacity reservations?

ProsperOps uses regional RIs which don't include capacity reservations. We favor regional RIs over zonal RIs because they support instance size flexibility (ISF), which improves savings for Linux/Unix shared tenancy customers. In our experience, customers favor maximizing savings over reserving capacity.

AWS has released a capacity reservation feature called On-Demand Capacity Reservations which is decoupled from RIs. We're planning to add fully automated support for these reservations, which provide the best of both worlds: ISF savings + capacity reservation. Please submit feedback to register your interest.