I have the PT-50C by Progressive Industries. (Portable unit) It goes where I go.
Shortly after purchasing it seemed to have a problem. Called Progressive, UPS to them, 2nd day return. A year later I seemed to be having a problem. Called them, sent it to them, and they fixed it. It was not sealed properly where the short cord goes into the box.
It has protected me several times over the last 3 years. I would not be without it, and the Progressive Industries support is fantastic.
RVUpgrades seems to have the best pricing.
Wayne MSGT USMC (Ret) & Earlene (CinCHouse)
2008 Winnebago Destination 39W
It is what it is, and then it is what you make of it.