There are certainly live AWS sites here in Australia. The main thing you have to watch with AWS, or any public cloud implementation, is the storage configuration and performance for your DB.Out of curiosity when you say "...AWS is certainly running customers in production today". Does that mean that you have clients or know of clients that are fully running JDE E1 production in the cloud today?
You can mirror your environment (hardware & software) on the cloud with AWS and Azure (if you go with Oracle cloud for E1, your only option is Oracle db on Linux) - the only factor that changes is internet connectivity. As E1 becomes less bandwidth intensive, you should see similar performance. I doubt if you will see better performance.better response time as they have with an in-house database
I am not sure about Oracle's E1 Cloud, but with AWS and Azure, you have full control. You can export backups of your data out (and you should on a regular basis even if you don't plan on parting ways with your cloud provider). There is a valid concern, of course, of your data still being "out there" in the cloud somewhere after you have parted ways or switched providers - this raises a security/control issue.Lastly, what happens to your organization's data if you choose to part ways with your cloud provider?