(Closed) Free virtualization system. What to choose XenServer or Vmware ESXi?

Question

Xen

A small firm plans to provide a PaaS service. Starts with 3-4 clients. The question arose on which platform to start developing the service. So far, only free versions of Citrix and Vmware are being considered. Under favorable conditions, licenses will be purchased. OS in virtual machines will be mixed. Support for hot backups is required, not snapshots (I found a console implementation on Citrix). Support for mounting network storage. Forwarding USB/COM devices from the host system.
High Available support. Open for clarifying questions.
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Unfortunately, for financial reasons, I do not work in this company and the question can be considered irrelevant. However, if someone has any questions or suggestions, I will be happy to listen, or mark as a "solution to the issue"

Answer 1

I would shoot for such a question =)

Answer 2

It's not easy to get hot backups from free ESXi.

Answer 3

It is logical to stand on what you know, if you have not worked with virtualization, then it is logical to hire a person who has worked.

Answer 4

ESX is better, but more demanding on hardware.
Usually I choose this way - if the hardware pulls, then I install ESX, if the hardware is not compatible with ESX, then I install Xen.
But wherever there is an opportunity to upgrade the hardware a little (buy a card compatible with ESX), I refuse Xen there. Because he screwed up.