So long as stable also means "unchanging" (in the sense of no new machines are being deployed). Our biggest win from AWS was never having to think about DDoS; our second biggest win was never having to wait for our Ops team (who was very good overall) to have the discussions about how to deploy new hardware, new storage, etc.
I get annoyed when a new EC2 instance takes 2 minutes to launch now. That time used to be not productive to measure in hours.