My experience. I installed a stock ice maker in the freezer of the "stock" Dometic 9 cu ft fridge in my new Classic. Not difficult to do, either. (Of course, I had to pull the fridge out to do it -- but I had to do that anyway to wire in solar and 30 Amp Magnum MSH inverter.) The ice maker came with everything I needed except the 1/4 inch tubing and valve required to tap into the water system. I did this a couple of months ago and the ice maker produces just as much ice in my Dometic as it would in the home refrigerator. Ice makers are built with a thermostatic control that activates a mold heater (to release the ice) and a mechanism to eject the ice from the machine. Of course, there's also a solenoid valve that opens to release the water into the ice maker. The main factor with an ice maker is "does the freezer get cold enough to produce ice." My Dometic most assuredly does this, either when I'm on 120V or propane. (I did wire the ice maker into my 120V inverter circuits so I can make ice when the Dometic is on propane.) I also have a switch to shut off the 120V if I'm boon docking and am majorly conserving power. Bottom line: if your Dometic is healthy and can do a hard freeze on food, it'll do a hard freeze on ice. Total cost of the ice maker and all the fixings is under $150.
"SilverLeaf II" 2015 30' Classic
2014 RAM 2500 Laramie 4x4 CC w/6.7L Cummins
WBCCI # 3430-Unit 21