I recently went through all of this including the confusion. I was interested in a 4 light timer by green-air that advertised it ran 4 1000 watt light @ 120 on a 40 amp breaker. I was bewildered that they would push it that high on the 80% rule, it took me a while to grasp. I had the timer wired in on a single pole 40 amp breaker with 8-3 wire, junction box in the middle and grounded. It works great! All lights going on and off smooth as butter. I am guessing something in the timer makes it worth $325. When turnign on they all turn on at the same time but during bulb warmup you can tell there was a small delay.