Ranked in these QuestionsQuestion Ranking
Pro Easily scalable
There's no cap in storage or traffic. Costs is based on usage.
Pro Super cheap with a year's worth of free service
S3 storage costs $0.03 per GB and gets cheaper the more is stored, PUT, COPY, POST, or LIST requests are $0.005 per 1,000 requests and GET and all other requests are $0.004 per 10,000 requests. And with some restrictions is available for free for a year.
Pro Supports custom root domains
To set up a custom domain, Amazon Route 53 has to be configured as the DNS provider with the domain registrar, two buckets have to be created and configured with the name the same as the domain - one including, one excluding www. A more in-depth explanation can be found here.
Con No SFTP support
Amazon S3 does not have SFTP support, instead the S3 web interface has to be used.
Con Unpredictable monthly charges
Since costs are determined by usage, they vary month by month.
Con Confusing web interface
Amazon S3's web interface is quite confusing, especially for first-time users, but there are many tutorials online that help beginners to set up a static site on S3.