The downside of the Midland WR-120, which I use myself and consider it one of the best consumer models available, is that if you let the backup “AA” batteries die and the unit loses 120 VAC power to the Wall Wart, all of the programming including the SAME Code(s) is/are lost. For a few pennies a unit more, Midland should create a new model with nonvolatile memory.
For that reason, especially in a commercial application, you may wish to investigate the commercial models listed on the NWS website at:
This is especially important where many lives and liability may be at stake. I would hope the more expensive commercial models are much more robust and feature rich as compared to the Midland WR-120 model.
Dave K4EET