To reduce the number of cycles on the power bar I have my range set at about 2 degrees and I have the heater matched to my tank size 250 watts for a 90 gallon. The tank cools slowly from 80 to 78 over about 3 hours and the heater is turned on for about 2 hours to slowly reheat back to 80. There are 4 to 6 cycles per day -- so there is very little 'stress' on the power bar.
I should be long planted by the time the power bar fails for this reason.