Rick and Karen, this link tells you about the one we bought:
Portable Surge Guard with LCD Display, 50 Amp - TRC 34850 - Surge Protectors - Camping World
We have used it on our 5er for 2 years, now Bertha 2 years and feel it has been a good investment. As for the hard wired units, I can certainly see advantages....it is always inside out of sight of thieves. But, with my unit, I can easily check the lights periodically. Either system may have units that go bad, but that would be low on my concerns. The customer service and support has been very good.
The big item on my list is the CG shore power.........is it clean and wired right.
Darrell