I feel the best in surge protection and power protection is provided by Progressive Industries.
http://www.progressiveindustries.net/ems_pt50c.htm
I purchased the Progressive Industries EMS-PT50 portable unit in 2003 and have used it since then. It took a direct surge from lightning when we were at a CG in Tenn and it saved our coach from any damage. Most RV's around us had most of their electronics fried along with refrigerator electronics.
I called Progressive Ind. because it had an error code after that and they had me sent it to them.
They replaced the entire unit free of charge.
I also like the way it checks to make sure the wiring and power requirements are correct before it switches on the power to the coach. It also monitors the voltage to make sure it is not to high or too low.
It is a little pricy but it is a lot more than a surge protector. I installed a plug in the cord inside the compartment so that I keep the unit inline inside the compartment just for it's security and my piece of mine.
I never plug in anywhere without it.
Ron