I have the Heki on my NL and if I had a choice of it I would not have it again. It is just to fragile. You are not supposed to complete close the shade on it in the sun as it over heats in the dome area and cause problems. Only close it to 2/3 of the way closed, in the hot summer sun it causes the cab over to get very hot. Also if you are not careful with the screen and go to move it back and you unlock it and it snaps out of your hand and just about breaks as it winds back up. The handle on it is not big enough to really get a grip on it. If something breaks the parts are hard to get and they are expensive. If you break the dome on it from what I have seen it cost almost as much as the whole skylight.
If it was me I would just have them put on an escape hatch which is the same style as a regular vent except bigger. This give you another escape route or a Fantastic Fan with a rain sensor on it. This way you can leave it open at night and not have to worry if it starts to rain as it well close itself.
Everything I have read on the 2 fridges I would take the Danfloss compressor fridge. Just make sure you have enough solar to supplement the additional power needed. Of course if you carry a small generator then that takes the place of solar too.
This is just IMO.
