Brian from Backblaze here. In general we are shooting for about the same reliability as Amazon S3. Backblaze is really transparent about our redundancy and pretty much everything we do. We use 17+3 Reed Solomon across 20 computers in 20 different locations in our datacenter. You can read about it here: https://www.backblaze.com/blog/vault-cloud-storage-architect...

Also, we are the only company we know of that releases our drive failure rates. We release them quarterly, here is the most recent failure analysis: https://www.backblaze.com/blog/hard-drive-reliability-stats-...

And for the record Backblaze only has one datacenter. This bothers some customers deeply so if it is a show stopper definitely don't use Backblaze B2. We just want to be transparent about what we do and what we don't do. One idea is you could use B2 as a primary copy of the data, and make another copy into Amazon Glacier in case the Backblaze datacenter is hit by a meteor (or a terrorist attack or an airplane crashes into it).

Oh, I said this elsewhere but I have a lot of confidence we won't lose your data, we've been perfecting that for 8 years. What Backblaze DOESN'T have much experience in is serving up viral videos and the CDN (Content Delivery) layer. I'm looking forward to that layer, I think it will be fun to polish, but especially over the next few months of invite only beta anybody using B2 needs to be able to work with us to get the kinks worked out.