Questioning the adequacy of certain quantum arrival-time distributions

It is shown that a class of exponentially decaying time-of-arrival probability distributions suggested by W{\l}odarz, Marchewka and Schuss, and Jurman and Nikoli\'c, as well as a semiclassical distribution implicit in time-of-flight momentum measurements, do not show the expected behavior for a Gaussian wave train. This casts doubts on the physical adequacy of these arrival-time proposals. In contrast, the quantum flux distribution (a special case of the Bohmian arrival-time distribution) displays the expected behavior.