So we are using AutoSPInsaller to provision SharePoint in an Azure based lab and it is taking several iterations to get it to our version of 'right' so we were looking for a way to pull a snapshot of a VM. there are a lot of steps that are still manual, so it I nontrivial to get to the state we want it in to run AutoSPInstaller. however, there doesn't appear to be a quick snapshot mechanism. The closest thing is to Save a VM Image which looks something like this:
Save-AzureVMImage -ServiceName "MasterClass" -Name "MasterClass"
-NewImageLabel "This is it"
The big drawbacks are that the VM must be off, and it is removed after it is copied.