Thanks for this information.
I have upgraded to Win 10. Prior to the upgrade I made vhdx files of all my VMware Workstation guest machines using the SysInternals Disk2Vhd utility.
I then uninstalled VMWare Workstation and completed the upgrade from Win 7 Pro to Win 10 Pro (64 bits).
I then enabled the built-in Hyper-V option in Win 10 and created virtual machines using the vhdx files I'd previously created.
To be honest, I haven't found anything significantly missing from Hyper-V compared to VMware Workstation, or at least, in the way I use it. The vhdx files seem to only support gen-1 Hyper-V machines but that may be the definition of the original virtual disc in VMware. Either way, the Hyper-V machines are fine for me.
I may return to VMware when it's Windows 10 compatible but to be honest, the benefit of Hyper-V is that it will always be compatible with the current version of Windows because it's a core part of the current version of Windows. That's a big advantage and, as I've said, I don't notice any significant performance or functional differences between the two environments.
Call me a traitor if you like .....
Thanks for taking the trouble to respond to my questions. You helped me come to the solution that works best for me.
Pete