I've installed and used both cPanel and Plesk on my dedicated servers in the past and I truly enjoyed the features and simplicity of cPanel (specially the auto-update feature in WHM), recently (a couple of months ago) I also tried a beta version of the open-source OpenPanel and although it looks really nice I found it kinda limited in terms of features, such as automatic system updates, automatic backups and the ability to add addicional hosts to the MySQL allowed clients list - just to name a few.

Besides OpenPanel, I'm aware of Usermin, Webmin, Virtualmin, ISPConfig, VHCS, web-cp and FlexCP - although I've never had the opportunity to try any of them before... Are you familiar and recommend any of these?

It's been a while since I managed a dedicated server and I'm wondering what would be a good hosting control panel for me, preferably a free / open-source one that has similar features / usability of cPanel.

I appreciate all input, thanks! =)