The quartz movement is generally
thought to be durable than its mechanical counterpart.
It is
without a doubt more accurate.
Omega claims a battery life of 27 to
36 months, although I've heard among actual users and from authorized
dealers that 2 years tends to be the upper limit. In either case, you'll
still need to have the
watertight integrity of the watch tested at least once per year.
Omega Seamaster 2561.80 is the
mid-sized version of this watch. The 3 to 4 millimeter difference in
lug-to-lug dimensions can be significant on smaller-sized wrists. Yet at
94% the size of the 2541.80, the 2561.80 is so exactingly scaled that
the casual observer isn't likely to know which you've chosen to wear.
In my opinion, this is more credibly
the watch Q-Branch would have chosen as a basis to equip with gadgets
for issue to a field operative.