Product review (5 stars): Whirlpool Ice Maker kit.
I was hesitant on purchasing this replacement kit for my Whirlpool refrigerator, due to the cheaper cost.  But upon it's arrival I was pleasantly surprised.  Appears to be a quality constructed kit, with a plethora of additional-if needed wiring harnesses (which I didn't need any of).  After installation I gave it 2-2.5 hours (time for the thermostat to calibrate I assume) and it powered up the water valve, fill the tray and with in a little bit of time I had ice cubes.