Product review (5 stars): Fortunately, a full replacement isn't terribly expensive so I ...
My original lasted about 5 years.  What fails on these units is the snap action thermostat (snap switch).  It's a shame that I can't find one with the correct form factor on e-bay or Amazon at a reasonable price.  This should be less than a $10 fix.  Fortunately, a full replacement isn't terribly expensive so I bought this.  I will hold on to the old unit until I can find a thermostat I can make fit so that I will have a spare.  One thing I did this time around was adjust the water trim screw such that 100mL of water is delivered.  The last unit was only delivering 76.  This should result in slightly larger cubes which translates into less cycling and somewhat longer life. Just weigh 8 cubes with a spice scale or let them melt and measure the volume. 100mL = 100g