Seems like you're only causing yourself possible trouble in the future by creating version 8 VMs if you have the ability to use the newer ones currently. If you don't have the ability to create newer than version 8 hardware VM because you're using ESXi for free then how is it an issue at all?

If you can create an 8+ hardware version VM you can still manage that VM as if it were a version 8 VM in the C# client and only go into the web client if you want to use the newer functionality. I don't know of a situation where you would be able to create a newer hardware version VM and wouldn't because of the issue above. You can manage newer VM hardware versions than version 8 with the c# client I've seen this mentioned a few times lately on SpiceWorks and this information is out of date.

We stick with hardware version 8 for that reason, so we can machine using vSphere Client with ESXi 5.5 The trouble with the free version previously offered is that managing any virtual machines created with new virtual hardware type requires the Web Console

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