If I crash landed in an airplane and was stuck in a deserted island without running water and electricity, at least I'd be able to tell what the time is at night and not have to maintain a calendar. Thus, I would need a perpetual calender minute repeater wristwatch! Out of those, the 5074 floats my boat!
Boy Scout Motto; "Be Prepared" That's a great excuse for purchasing a 5074!
The 5074 is not water resistant. Perhaps I should get a 5140, but then I won't be able to tell what the time is at night.
In any case, love them all! A calendar would be very necessary!