For AWS Savings Plans vs Reserved Instances, the default answer is: buy a Savings Plan, not a Reserved Instance. The exception is OpenSearch, Redshift, and (until December 2025) databases, which still need the older Reserved model. That is the whole decision. For most teams a Compute Savings Plan is the right default: same discount as a Convertible Reserved Instance, far less to manage, and it follows your workload across instance families, regions, Fargate, and Lambda. The cases where a Reserve...