The best features Antivirus for Amazon S3 offers include that it is really a built-in feature which is really great, as you don't have to do anything extra, there's no operational complexity or cost overhead associated with it, and because it's a managed solution, it's easy for us to configure policies as S3 buckets are created globally and make sure they have the necessary virus protection as needed. The simplicity and ease of policy configuration have helped my team day-to-day because, as it is part of the AWS ecosystem, I don't need to really hire a separate skill set to configure this service, and moreover, if I use the console, all the features are available to me at a click, and I can also programmatically control it, making configuring the antivirus part of setting S3 objects rather than setting up a separate service altogether on top of S3.
