From a standpoint of leverage, side laterals might be the worst exercise, as evidenced by relatively little amount of weight you can use. Most of the time people go too heavy, putting a lot of stress on the shoulder joint, and end up injured.
I don't see them as a worthwhile exercise, as is the case with most isolation movements.
I do agree that shoulders respond better to higher reps. Basketball players tend to have good delts even though many don't lift. Why? Because they spend a lot of time with their arms raised and their delts flexed.