Once you calculate what it would cost to replace all your electronics (tv, radio, dvd player, fridge, water heater, furnace, AC, etc) consider a surge protector sort of an insurance policy. I would recommend not just getting a surge protector but an EMS 30AMP power protection unit from Progressive Industries. An EMS unit will do more than just protect your camper from surges. They make both portable and hard wired units. Link:
http://www.progressiveindustries.net/Here's a link to a recent thread:
http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/28168901.cfm