We're getting ready to virtualize our existing Zimbra infrastructure. I'm curious if the 8.0 Appliance install scales to thousands of users. When we need more capacity can you use the appliance through VMware to create and manage as many VMs as needed to serve lots of users?

Is the traditional ZMPROV cli stuff still available with the appliance or is it all GUI and REST?

I'm trying to figure out the best/easiest way to virtualize our 10 physical servers with many thousands of users to VMs. The Appliance might make sense if it can easily add capacity as needed.