Human nature - people won't bat an eye spending $20K, $30K, $40K, etc on a trailer but wince when it's suggested that a $400 expenditure for a surge protector / EMS is a wise investment - go figure. :S I should know, I used to be one, but when I had the opportunity to buy a used TRC Surge Guard I jumped at the chance, remembering how the microwave oven in our KZ Spree had suddenly died for no "apparent" reason. :M I later sold that portable SG for what I paid for it and invested in a hard wire Progressive Industries EMS-HW30C. In the time since it's disconnected multiple times, for a variety of reasons, so knowing what I know now I'd never plug into shore power of any kind without it. ;)