Best Free Multi Site WordPress Administration

I manage a collection of about 30 business websites using WordPress. It’s certainly not practical to manage them individually, especially after the SoakSoak Zero Day disaster and the increased level of security needed to protect sites now days.
MainWP is the best free multi site WordPress admin utility I have found so far, and I have tried several.

Well designed user interface
Works 100% as far as I can tell
Large selection of premium Extensions*
Even more Free Extensions

Site Backup Issues
I have not been able to get site backups working as well as I would like, but that may be my lack of understanding the methods used by this tool.
FYI, I setup one of the primary site backup option called just ‘BackUpWordPress’ for a group of websites on a Go Daddy Managed WordPress hosting account only to have the plugins disabled by Go Daddy for security/performance issues. (had to be the plugins hanging when backups fail. Understandable.)

WordPress Security
With MainWP and the Ninja Firewall (no association between the two apps) I manage my WordPress sites with great confidence in the face of constant hacker attacks, sometimes hundreds a day!

WordPress Site SEO
If you require anything more than bubble-gum/Google Best Practices SEO for your websites, MainWP steps up like a true power developer with a free Spintax compatible Content Spinning Extension to assist in the war against duplicate content penalties all serious webmasters face.

5 Stars Overall
I give MainWP 5 stars overall considering my high level of of technical requirement and the complexity of the task at hand.

4.7 Stars Technically Speaking
But from a purely engineering perspective, I would rate it at about 4.7 stars. If you find anything better than this, please be sure to let me know!

* I have not tried any of the premium Extensions yet which says a lot for the Free functionality of this administration tool.