The height of the enemy, player and collisions is 32px. Does anyone know technical details of the line of sight behaviour?
I do know it's a bit quirky from when I attempted to use it for a roguelike top-down dungeon view. It would detect one side of a corridor that the character was in, but not the other. Quite vexing. I even tried centering the hotspots perfectly by making 31px objects instead of 32. Gave up on it eventually. That said, I think it should work fine for this.
What did you mean by 'collisions is 32px'?
Anyway, the one big variable that I noticed was the accuracy attribute of LOS. If the LineOfSight accuracy is set to 10 or below, it should work fine. I did a test of a similar setup, and it performed poorly with larger accuracy numbers, though.