There's nothing wrong with insurance. It can make you feel comfortable. I do get a flu shot every year.
It seems that many of today's electrical
components are naturally immune to over and under voltage.
For example, the AC electric portion of must refrigerators and electric hot water heaters are simply heating elements and probably could care less about over or under voltage. Ditto for electric heaters.
The only item of significance left is the TV and computers. I suspect that all of them have an input switching supply that protects them from anything short of a lightening strike. To protect our computers we generally only charge them when we're around in case of a superious lightening strike while away.
The remaining item in our trailer is the converter that we rarely use because of a solar panel
. I suspect that it also easily can withstand any thing short of a lightening strike.
For me the purpose of a device like this would be to protect against lightening and not over or under voltage.
In our 11 years of RVing amounting to well over 2500 nights on the road, we have never had an electrical
On second thought, as I get ready to send this, probably the moxt vulnerable component is the air conditioner. It would not like undervoltage.