Probably best to ask on the "ATC Issues" forum on PPRUNE.
I believe it varies between units but I have been told that the controllers may use different colour strips/holders for outbound, inbound and transiting aircraft etc. So if your first call gives them a clue they can start entering your detals in the correct place. How it impacts units where it is fully computerised I have no idea - hence my suggeston to ask on the ATC section.
Personally I would include "basic service and zone transit" if passing through, or "inbound to xxx" if landing in the zone. Of course if transiting when one enters the zone it becomes a control service of some sort since basic aplies only outside controlled airspace. But the controller will advise what he is giving.