Product review (2 stars): Loud popping sounds "can be expected"
Every time the compressor turns on, the refrigerator makes a series of loud popping noises.  I wrote the distributor, and this is what they said:

"The following describes the kinds of sounds that are to be expected:
Rattling noises may come from the flow of the refrigerant or the water line.
Items stored on top of the kegerator can also make noises.
The high efficiency compressor may make a pulsating or high-pitched sound.
Water running from the evaporator to the water bin may make a splashing or sound.
As each cycle ends, you may hear a gurgling sound due to the refrigerant flowing in your kegerator.
Cracking or popping sounds are caused by the expanding and / or contracting of the cooling coils."

I am not hearing any of the other sounds that they say can be EXPECTED.  I work in the air conditioning/refrigeration industry.  I have never heard this kind of noise coming from a cooling coil, and if a coil is making these sounds because of expansion/contraction then the coil is being physically stressed -  this cannot be a good sign for the longevity of the unit.  Do not buy his unit if expect it to be quiet.  I will update post if the unit breaks.  Other than that...it is working well, but I will have to move it to the garage if I want to sleep at night.

After further correspondence with the manufacturer, they shipped a replacement unit!  Before it arrived, I noticed that ice had built up behind the evaporator coil on the back wall inside the unit.  I defrosted it, and it no longer makes the popping noises, which were apparently do to the ice either expanding or cracking.  They say that it does NOT have a defrost cycle, and requires manual defrost.  I will live with that, and ship back the replacement unit.  Might upgrade to four stars if I can limit the ice build up by allowing better air circulation.

Update:  I defrosted the unit and returned the replacement unit, which turned out to be a mistake.  Within a couple of days of plugging it back in, it started the loud banging noises again.  I would definitely not buy this again.