That's great if your schedule fits your sleep schedule, but I'm not sure that's very common. A product that can wake you up in time for your schedule and avoid waking you in the middle of a sleep cycle could make it easier to make due with less sleep. At the extreme of little sleep required for newborn overnight feedings, for me, three hours of sleep is significantly worse than two or four. That said, sleep cycles tend to be shorter and shallower as the night goes on, after several hours of continuous sleep, the penalty for waking up at a bad point is not that bad.
