G'day David, we have just picked up a Waeco 50lt and took it away recently into the kuitpo forest. It ran 72 hours on the Coolpower 36 battery pack we got as part of the deal
The outside temp was way below that of a summer day obviously at this time of year, but we were happy enough with that. I believe an independent survey carried out by the csiro or similar asked all the fridge manufacturters to send them a couple of products each for testing and the Waeco came out in front overall for power consumption - Also the material the Waeco is made out of does not absord heat, that was enough to push me into a Waeco.