[deanhills]

I usually advocate to not use any control panel to host personal sites on a VPS. I mean if you operate a VPS... you probably should know how things work the CLI way and using no control panel usually saves a lot of resources inlcuding RAM, disk space, bandwidth and also money if a paid control panel would have been used. If you really need one I wouldn't use this precooked options like the one from Virtualizor or other installers that are around. It is better to install the panel manually as per documentation of the corresponding control panel.

In my own experience this depends on the control panel and how the panel has been set up - and also the specs of the server and VPSs.  I'm not a big fan of Virtualizor, but if it is set up correctly by a Tech Admin who knows his server very well, it can be set up with maximum benefit for both the server and for the users.  Also, with the very large specs we get these days with VPSs it shouldn't be the issue it used to be when RAM was 512MB.  When we were running Virtualizor for the first time in 2014, my VPS had 512 RAM and 10GB disk space - and the panel did make it feel slower - your point of view would have been very valid then.  Then when my RAM was increased in 2016, as most VPS hosts seem to be able to do these days to first 1GB RAM and then 2GB later on the panel was noticeably faster.  Thing is most clients are beginner Linux users and a panel, depending on how it has been set up, can be a huge help for both the users as well as the host.  

The best ever panel I've ever used has been with HostUS.  The Breeze Panel is lightning fast - and has been developed in-house to cater for HostUSs specific needs. My VPS only has 768 MB RAM which to me the fact that the Breeze Panel works so fast shows that the whole thing has been developed and set up by Tech Admins who know what they're doing. The focus in it is also beginner users and to get them to harden the security of their VPSs with tools in the Breeze Panel that have been specifically designed for that purpose, like helping inexperienced clients set up keyless entry and port number change from their panel.  With Virtualizer it's a one size fits all type panel with loads of icons and tools that aren't used - a waste of resources for sure.  You need an above average shrewd tech admin who can set it up properly.  In our case we had someone like that - who made minimal use of all the tools in the panel.  He did however load all of the important OS templates - with the exception of Windows.  When I first started using a VPS in 2014 I found the ability to reload my OS from a panel more than valuable.  Not sure how I'd have been able to learn what I learned without being able to reload the OS limitless times.  I wasn't even sure I wanted to use CentOS - and at least with all of the templates available, I could experiment with those as well.