We have one in our 21FBRS for 8 months. It works great , no issues of any kind. Stays true with a bubble level, but much easier to use. I mounted it on the divider inside the passenger side forward compartment. Wife turns it on when we start to back up so I can check initial level once I am backed in. Then we true up with the red Anderson’s. Sometimes those are a challenge on this trailer because the wheels are so close. I have been able to get within .25 of level in every site we have camped in. This weekend I saw the passenger side was 5.5” low, so I pulled up a bit and started at 3.5 low instead. I use this tool every time we camp, and highly recommend it. If someone is having issues, they must have a bad unit, because mine works exactly as expected.
2019 Flagstaff Microlite 21 FBRS
TOW vehicle- 2020 Ram 1500 , 5.7 Hemi, 3.92 rear end, tow package with trailer blind spot.
Max Tow capacity-8379 with full payload
Max payload- 1721