I like this one - https://ithemes.com/purchase/backupbuddy/
It is not a free one, but if you really, really want to protect your WP site - it will do the job! It even has a function to scan your site for viruses (I've never seen a back up plugin to had this!). Nice solution!
Here are its features: Back up your entire WordPress installation. Widgets, themes, plugins, files and SQL database - the entire package! Just like your laptop or desktop computer, you should be doing regular backups of your website. With BackupBuddy you can schedule backups and have them sent off-site to Dropbox, Amazon S3, Rackspace Cloud, an FTP server, or your email. Or download them right to your desktop. You can also use their own storage space (1GB) :-) See here:
the plugin has 4 version and presumably prices: $80, $100, $150 and $197
HOWEVER! THere are some coupons available! :-) just search online...
Hope you will find a solution for your WordPress backing up conundrum! Good luck!