Josh26, ESXi 5.5 does not actually create VM's with V. 10 hardware.
You can not select it in the creation process either (GUI) . Highest versjon you can select is V8.
So when you create a VM it s max HW V. is 8.
You have to manually "Upgrade Virtual HW" to 10, to get a v. 10 HW VM.
Anyway, if you dont have vCenter or vCenter is unavailable for some reason, you can not edit v. 10 VMs! 
I think VMware really messed this up. Either vSphere client should be able to edit v 10 VMs, or they sould provide a web interface directly on the host.
Unless they are phasing out the free ESXi.. To me it seems like they are heading that way, since they releasing 5.5 with this "issue".