I have a Minn Kota with 74 lb. motor but am switching to a Riptide AP65 (Riptide Autopilot is not available in 74). I rarely ever run the 74 at more than 50%, usually 15-20%. Will I experience a significant difference. Boat is an 18' center console. Also, I have been told that the 65 series motor is quieter and uses less electricity. Any opinions?