That is pretty old, considering what S3 has changed in the past two years. In particular, it talks about reading S3's us-standard region from the East and West coasts, and that has evolved to where us-standard (which is really us-east-1) is now the same as all other regions when it comes to consistency (presumably because all requests physically go to the East coast now, but I haven't tested that):

http://docs.aws.amazon.com/AmazonS3/latest/dev/Introduction....

Fair point, I will update the AWS us-standard results and include Backblaze as well.

Per that AWS page, you might want to add an asterisk that you lose read-after-write if you make a GET or HEAD to the keyname before your first PUT. So checking if the object exists will punk you down to eventual consistency.

Thanks! We'll address this in our documentation.