I have no experience with the Waeco units, so I will not comment on them. I will say that my experience with the Engel units does not match up to the results of the test. I make a habit of measuring my total amp draw when I camp with my Engel MT45, and it usually uses about 12-15 amp hours in a 24 hour period. At 2.5 amps, a 50% duty cycle would be 30 amp hours. I am not sure why the authors believe that the Engel (Sawafugi) units are designed to run almost constantly. That would result in almost 50 amp hours in a 24 hour period.
Now it is true that I am mostly in mild climates high 80's during the day and high 50's at night, but I am not sure how they got the Engel to draw 2X the current as the rest of the fridges.