Ditto on the 5645's I also have used them for two years and no problems. I use 5625's, 5945's and JR8411's if there is a power drain difference its not enough that I can see or be worth thinking about. With my 33% Ultimate I have four 5645's on the ailerons, two 5945's on the elevator and a 5735 on the rudder. I have a 2700 mah Nimh in it and can fly eight 10 min flights in a day and have power left if I wanted to fly more. I'm trying a JR8611 on the rudder of my 33% Extra so far so good. Will most likely change my Ultimate's rudder over to one to save weight. An once here an once there adds up! BTW the Extra has Four 5625's on the ailerons.