Definitely recommend what with all the electronics in RV's nowadays. They have saved our unit from damage more than once I think.
This is the one i installed in our current van:
http://www.campingworld.com/shopping/it ... -amp/56406 It mounts inside the van so there's no theft worry. Lifetime warranty also & good price...
Here's another one:
http://www.campingworld.com/shopping/it ... -amp/58464 This is on sale at a very good price right now, and is what we used on our previous RV. These seem to be the one that's most popular out there.
Also, I never worried about theft as we never left the RV unattended for more than a couple hours at most, and if you leave and go anywhere, you take your power cord and surge protector with you. Your insurance would cover it anyway.
We were this last fall in a state park in Florida, St. George Island. There were no storms anywhere around. Sky perfectly clear. At 245am I woke up to our surge protector clicking on & off. It has a remote mounted led readout that I can see from the bed. It was reading a voltage fluctuation between 107v & 132v. Up, down, up, down, albeit slowly. The surge protector was protecting the the van's electrics from those high voltages, and cutting the surge out. This went on for about 10 minutes and finally quit. No idea what caused it, but I went back to dreamland not worried about it.....