Well just an FYI that if you attempt to do this from a Logon script you're looking for some real problems unless you have a very robust network and server.

Moving a PST during a logon script is going to put a LOT of data in motion at or around the same time. Also some people may have Outlook setup in their Startup folder which would then lock the PST from being copied/moved.

Also if you change a drive mapping to the location then the Registry for that profile also would need updating.

Just some more things to be aware of.