I've had one for almost two years. I've had to have the power supply replaced and the controller replaced. They claim it isn't made for offroad use, but mine works well on trips. Due to voltage issues, I run mine off a 150 watt inverter, but it runs for hours with the engine off. Get the bag for it off Amazon to keep it more efficient.
Every Day is a Good Day Surfing...Some are just Better Than Others
I am using it in my big rig, so its definitely not off road (although some of the interstates ride rougher than off road). For the price and for what I need, it works well. I also have an Engel in my Tacoma that I have had for about 6 years. In comparison, this one is not as stable temperature-wise. It will fluctuate from about 28 to 38 when set to 36, as I have it now. The Engel only varies a couple degrees, but it doesn't have a computer controller.
The size is similar, but slightly different proportions. This is shorter in length, but wider, so it fits better where I need it now. They are about the same height. The hinge is on the long edge vs. The short edge on the Engel.
The inside is arranged differently as well. The Engel has the compressor stuff all at on end of the cabinet, so the compartment and basket is floor to lid the same everywhere. I have the extra baskets for smaller items. The Whynter has the compressor in a bottom corner, so there are effectively two compartments, one deep and one shallow, with baskets for each. No physical barrier though. I use the shallow for smaller items.