There have been a number of SAS users who have had success installing various products within AWS. There was some content released at SGF last year related to this topic. For example, a white paper on hosting a SAS Grid Manager deployment in AWS can be found at https://support.sas.com/rnd/scalability/grid/SGMonAWS.pdf. A high level Tech Talk on deploying SAS in AWS can be found at https://www.youtube.com/watch?v=XHaLA7JSQyU. There are certainly security topics you should consider when deploying to AWS, specifically those governed by security groups and access keys. It should also be noted that going to the cloud obviously doesn't absolve you of all administrative tasks. Yes, it outsources your hardware and provides very quick ways to spin up machines running Windows and Linux. But you're still on the hook to manage and secure your software running in it.
I would be interested in hearing the experiences of others who have migrated SAS deployments to AWS or other cloud IaaS providers.