I have an Edgestar (Whynter) that has been running almost continually for the last 12 years, either on the road or at home. It has been 100% reliable without a single glitch. I also have an Iceco VL60 dual, that is great and built like a tank, and an Alpicool C30. Both are nicely made and hold the internal temperature very accurately. I would not hesitate to buy any of these brands again.
I also have and Engel 62 that has been less than reliable, and Engel's customer service is seriously lacking. I would never buy another Engel based on the experience I've had with this one. I know they make a good product, but if you have a problem . . . good luck getting any help from Engel.
Last year I decided to try one of the really cheap brands sold on Amazon. I bought a small Joytutus. Depending on what temp you set, the actual internal temp would sometimes be as much as 20 degrees warmer than what was showing on the display. It could be set as slow as -8, but it would never attain anything below 0. The company was very responsive to my emails, but was never able to adequately explain how to adjust/regulate it. It was pretty obvious English was their 3rd or 4th language. They actually did make a video showing the procedure to adjust the electronics, but they used a different model and posted the video upside down. Kind of hard to watch, and there was no narration along with it. I ended up returning it.
When I tested all of these refrigerators I made sure they had a large amount of thermal mass in them, used a remote temp probe in the middle of the compartment, and let them stabilize for at least 24 hours. That way I could compare the set temp to the actual internal temperature. Both Iceco and Alpicool maintained a temp within 1-2 degrees of the set temp. It's been so many years since I checked the Edgestar I don't recall how close it stayed, but it must have been acceptable or I wouldn't have kept it.
And, one more . . . . About a year and a half ago a friend bought an inexpensive Costway 53 and it has been reliable and working great.