I'm a consultant, and I architect solutions for customers by using Amazon EFS in other Amazon products. I am using EFS based on NFS version 4.
I have a customer who is using around 20 Linux servers hosting MySQL databases. Their storage is in Amazon EFS. So, around 20 Linux servers are connecting to Amazon EFS.
Before Amazon EFS, our customer was using EBS volumes in a unique EC2 instance to serve NFS servers. Now, these EC2 instances are not necessary. The productivity of the customer has improved by around 30% by using Amazon EFS instead of a unique EC2 NFS instance.
Its elasticity and flexible pricing are the most valuable. For Amazon EFS, you are charged based on the storage. It is also very fast and stable with a very simple and intuitive interface.
It could be better in connecting with Windows Server instances.
I have been working with Amazon EFS for around two years.
Its stability is wonderful. Our customers are very grateful because it has been working successfully in a very much acceptable way.
Its scalability is great. It is very fast. It is almost instantaneous. Our customers are small and medium business companies.
For this project, we did not need support. We didn't use professional or paid support. Amazon's documentation is very rich and helped us during this project.
Our clients didn't know any other solution like this. We, as IT consultant, offered the solution to the clients.
The initial setup is straightforward.
It has flexible pricing. You are charged based on your storage.
It a great scalable and stable solution, but just use Unix or Linux servers on-premises or in the Amazon cloud. I won't recommend using a Network File System to connect to Windows Servers.
I would rate Amazon EFS a nine out of ten.