I have used the 12V Cool Blue for a few years now including a pass through the tropics. I'm well satisfied with the cooling
unit. We have a spillover setup with about 3 Cu.ft. in the freezer and 6 cu.ft. in the refrigerator
. Both sections work fine. However, especially in the tropics, it runs a lot of the time to keep the freezer frozen. It is more a comment on the efficiency of the box itself than the efficiency of the Cool Blue. My box is large and leaky - there just isn't enough insulation
and I'm not willing to tear the whole corner out of the galley
it. I have a DC genset, so just run it more often in the tropics. I'd say the Cool Blue is eating about 8 amp-hours on average with the inefficient box I'm using. It is quiet and reliable and we didn't really suffer with running the genset twice a day.
Spending time on re-insulating the box is the best way to get satisfactory results from any refrigeration system.