In the real airplane I mostly use it for descentplanning.
In the sim with 1eng F/D off approaches it makes things much easier. Pass the descent point, lower the nose to put the FPV onto the desired glidepath while simultaneously setting the N1. On the sim printout, you will have a perfectly straight line hitting the all the altitude gates within 10-20ft with almost no input at all on the column wheel regardless of the headwind. If the instructor says FPV-off though, it tends to look a little different
