Take one arm or the other and hold it across your body so that you're able to feel the upper pec front delt tie in area.
With the free arm tense and move your arm through the range of motion that a front press would involve. Now Take your free arm and hold in the behind the neck move and move through that range. If you are moving through both movements properly you should feel less frontal delt involvement with the behind the neck move.
Both moves are good movements, but, IMO, they hit the shoulder differently.
One of the issues taht I see with people performing front presses is that they perform the movement much like most people perform a bench. They have their arms at too wide of an angle and are trying to isolate the delt. The press is not an isolation move.
Done properly a standing press is not that far removed from the bench, or from the close grip bench.