I'd like to post a feature request here on these forums to see if you are aware of this new feature, and to get feedback from other users who may be in support of this new feature as well.
A little over a month ago, Amazon S3 released a new feature called Amazon S3 Reduced Redundancy Storage (RRS). Read the details here.
In a nutshell [emphasis added]... "S3 was built to have 99.999999999% reliability, meaning if you store 10,000 objects with S3, on average they may lose one of them every 10 million years or so. Not every application actually needs this much durability. In some cases, the object stored in S3 is simply a cloud-based copy of an object that actually lives somewhere else."
This is exactly the case with how W3 Total Cache handles files with Amazon S3/CloudFront so this would be a perfect feature to add to the plugin. IMO, it should be enabled by default, with a checkbox to optionally turn it off if the user would like the added reliability.
The main reason why I feel it should be on by default is this:
RRS pricing starts at a base tier of $0.10 per Gigabyte per month, 33% cheaper than the more durable storage.
Saving W3TC users who use Amazon S3/CloudFront 33% off their monthly bill would be a welcome change I'm sure.
Hopefully this won't be too much of a hassle to add as this just requires adding a "x-amz-storage-class" header with the "REDUCED_REDUNDANCY" value to objects uploaded to S3. Unfortunately, objects already uploaded will need to be re-uploaded to take advantage of this feature.
Thanks for an amazing product, and here's to making it better!
PLEASE NOTE: This only applies to the cost of storing objects in Amazon S3. This does not apply to the cost of bandwidth into/out of S3 or CloudFront. If your site has only a small number of small files cached into S3/CloudFront, then you won't see significant savings from this feature once added. Your monthly cost of storage will still go down 33%, but it's usually the bandwidth used that is the majority of cost for users in this situation.
However, users who have a large amount of larger objects (such as high-rez images and video files being pushed to S3/CloudFront) will see significant savings from this feature.