In Essence, all the above listed softwares are do virtualisation very well.
ProxMox based on KVM, and SolusVM have many option, KVM, OpenVZ, ...
This comparison is came from my experience with a technical view.
Hyper-V: This is a Microsoft production, Microsoft doing something well nowadays since Im preferring Unix-Like, Microsoft did some flavors to me. But Hyper-V is well integrated into the Windows itself, and works nearly out-of-box.
Able to run various operating system, but management is a bit difficult.. Similar to an Active Directory management.
I missed some important functions and needed to hack something even in registry?! to let me work. I dont recommend Hyper-V for newbies, even for production. Hyper-V is for Windows magician.
VMWare: VMWare is an absolute market winner, however the newest version have WEBGUI, but managing under Windows is the best fit for experience. VMWare have multiple licenses and as I know it have a free version too.
VMWare is for study, production and for big enterprises. Using VMWARE for mass hosting is not recommended due to high fees. VMWare know everything, managing is less difficult as Hyper-V "and feels-like I can create my own internet thing". VMWare is fast, runs very well, I did not experienced any problem at all. The only thing is not always compatible with the host hardware and you have to enter by SSH to investigate issues with a minimal space you have, due VMWare uses their own "linux" system on nodes.
SolusVM: SolusVM is a big idea with a lot of bugs. SolusVM is a paid VPS Hosting Admin Panel, you get everything you want, it can be automatize, its for VPS Hosting. Virtualization technology is given, so I cant write good or bad, from KVM or VZ, and etc.. but the WebGUI itself is a great, but having Bugs. I dont intended to list here any details about bugs, the major issues that I experienced are: Resource Calculations are broken, my system had: - 3,545 GB RAM.
Nodes sometime looses communication with frontend and its can cause a bit mess. NoVNC SSL problems... But I could recommend for VPS Hosting, with these kind of bugs, overrall its a perfect solution.
VirtualBox: Well.. VirtualBox a very lightweight and the most user-firendly solution to virtualize. Its working out-of-box, and totally free, some-extras: (RDP, USB3, etc..) is available for non-commercial use only. This is Strange thing because sometimes faster than VMWare and I used to enterprise/production-level too for years, without a single trouble. This software is lack any remote control and since its available on Windows, Linux, (FreeBSD but very limited, dont use under BSD) but it have a third party (PHPVIRTUALBOX) that may solve your issue, but.. err.. nope. You should manage remotely by VNC or RDP or X-Forward. It knows so much, but not for mass hosting.
Its highly recommend for home, study, SBS, even in enterprise-class levels, very stable.
ProxMox: Surprise! I seen ProxMox in very early stage and then I said, noo-way. But currently Im running under it.
So this is a Big Come - Up and a suprise, Proxmox is free but it have their subscription option to get some support, and since its a great software they should be get this small amount of cash. The VM HOST Running under Debian, currently Debian 10. And not limited so you have all the control over the machine this is great anyway.
Proxmox have a good Web interface to manage servers and uses KVM technology. I dont want to say detailed review about KVM here, its works well support almost all operation systems. But Proxmox have option to cluster and already know the ZFS Filesystem and handles it quite well. So ProxMox is exactly what I ever needed and sometimes it have some bugs (never ending tasks, hung up) the functions are priceless. Proxmox can handle clusters, High-Availability so the most main features that VMWARE does, and console view, containers... ProxMox is ideal for SBS, VPS Hosting, Office.
My TOP3 rankings:
- ProxMox (Ideal in any case)
- VMWare (Enterprise, Study)
- VirtualBox (Ideal for smaller things)