Earlier quoted context omitted.
Not to mention that if Cloudflare CDN was in front of it this traffic would be free.
I'm skeptical of the number of 500+ MB files the CloudFlare CDN would actually cache... Does anyone have any numbers on this?
Of course, you can trick Cloudflare into caching your large media assets using some funky Page Rules... but I wouldn't suggest it. Mostly just for moral reasons. If you have that much traffic, you should be making some money off it and then paying Cloudflare with it!