I think it depends upon your own circumstances.
As I understand it...
Leave Mil and rejoin Mil, you'll lose out as pension offsets wage.
Leave Mil, join Civ, leave and rejoin Mil - You don't lose Pension.
I'd seriously look at doing a paper-round for a month or 2 after leaving, just to get a NI/Income Tax credit from an non-Mil job.
However, this may depend on leaving at pre- or post- 22yr point (for ORs)
Last edited by unclenelli; 2nd Feb 2013 at 18:38.