Why use sysprep for Sharepoint 2010 Developer VMs?

I have read several articles about creating a Sharepoint Developer VM. They all say to "sysprep" them. Why (exactly) must the sysprep be done?开发者_JAVA技巧 What kind of problems (and why) will we run into if we don't sysprep them?

(I suppose what I am asking is, what would be the difference in doing "sysprep" and just bringing up the VM, changing its Name/IP, reboot then install SP?)

I've had success in the past with just copying Hyper-V vhd's as a method of cloning VM's - however, I now use sysprep when cloning any of my machines as it's been mentioned as a best practice in many places. And, it does some nice things like allowing you to cleaning up a bunch of stuff that I don't want to duplicate and letting me choose a new name for the machine on boot. From MS Sysprep Technical Reference:

Sysprep prepares a computer for disk imaging or delivery to a customer by configuring the computer to create a new computer security identifier (SID) when the computer is restarted. In addition, Sysprep cleans up user- and computer-specific settings and data that must not be copied to a destination computer.

And you may want to read Russinovich's post on The Machine SID Duplication Myth (and Why Sysprep Matters) for more good explanation of how SIDs work and the very last paragraph has another reason for going this route:

Note that Sysprep resets other machine-specific state that, if duplicated, can cause problems for certain applications like Windows Server Update Services (WSUS), so Microsoft’s support policy will still require cloned systems to be made unique with Sysprep.

Good luck!