+1 on the Progressive Industries EMSHW30C 

I installed the progressive EMS-HW30. Thats one of the more popular models being used. It is hardwired into the camper, so you install it once, and forget about it. It will not allow you to hook up to bad, or miswired power supplies. It continues to protect you the entire time your plugged in, wether your gone out, sleeping, or sitting by the fire. It also protects you from a "hot skin" condition, which can kill someone that touches the trailer. For just over 200.00 dollars, is it worth this protection? I think the math is simple. Ofcourse if you plan to only boondock, and never ever plug into anything, you don't need it, but what are the odds you'll never plug in.  I would recommend the hardwired unit, as mentioned before, its a onetime thing. No remembering to get the portable plug, or, i left it on the work bench at home, or sombody stole mine.  There will be no fumbling in the darkness, trying to find it in the pass thru, the hard wire is just the best way for me. Ok, now you know.

Recently I purchased a 2017 R-pod model 179 and now I'm looking for a surge protector best suited for this size camper. I've seen recommendations on the forum ranging from $50 to several hundred dollars. How do I know what is best suited for the 179? 

For example, Surge Guard has a 30A model that automatically shuts off the power when ground faults are present and it offers 510 Joules of surge protection. It requires manual reset after a ground fault. A convenient handle makes unplugging from the power post easier and safer and it has a 10/3 AWG weather resistant cord. At $67 it looks like a good deal from Camping World. In contrast, the SSP30 by Progressive Industries is larger and sells for $110. Some more expensive models can even be locked to your power hookup. Can someone please provide some practical advise on what I need?