Should I deselect the "Synchronize with an Internet Time Server" checkbox under the VM's "Date and Time -> Internet Time Settings" tab if the "Time Synchronization Service" for a Hyper-V-based Virtual Machine is enabled?

One of the Integration Services that Hyper-V provides is the Time Synchronization Service, which can be enabled/disabled by going to a VM's Settings->Integration Services setting in the Management section. I believe this is checked by default.

When you install a Windows Server 2008 OS in a VM on the Hyper-V server, it comes with the "Synchronize with an Internet Time Server" option set, pointing to "time.windows.com".

I'd think that if the parent Hyper-V server is set to one time server, and the child VM is pointing to a different time server, there would be a momentary blip if the two are not spot on with their times when the synchronization services run.

So the question is, which time sync service should I use? I'm assuming not both. And what is the advantage of one over the other?

Note: This question assumes that the machines are not joined to a domain. If they were, the machines would also try to update their time against the domain controller with the primary domain controller role too, right?

Thanks!