Tonypatch
331
With a 3940....
....you are buying classic PP style, a classic model, absolutely timeless, at a moderate price for what it is. It cannot become "outdated" because it already is. The 993 of PP.
With a 5140, you are buying "a modern interpretation" of said model. For what its worth. With a dial that has been commented on enough here, not really much in its favour. If you want, like a 991R - much more expensive than the model it draws its inspiration from, offering...."more" (in the eye of the beholder).
3940 all the way.