Thanks you for that - the back of your watch is identical to the Optima and the face is very similar but has no seconds face at the 6 o'clock position as yours does, same AM & Crown then the 6b/234 nos but no stores nos!
I do prefer the Optima and presume that it is earlier than the Omega becuase of the AM & Crown (no date on the Optima) but the Omega 6b/159 has a service issue nos and date, 1944, but is later......
I always thought that they discontinued issuing 6b/259's after 1941 - is this correct?
Oh well....decisions to be made!
O/C RAF at War