I want to say I paid $220 w/display from amazon. Then a few bucks for a few feet of Romex wire from HD or Lowes.
Part of your decision should be "if I had a hard wire,where would I put it? How hard will it be for me to put it there?"
There are some pics floating around here (search: surge protector) of owners that included plugs on both sides for easy removal. Mine was an easy install as power comes in to my TT in a storage compartment so I just put it there.
I also hear that PI has awesome customer service and lifetime warranty.
2014 Stealth Evo 2850 "Woodstock"
2011 Toyota Tundra Rock Crawler TRD 5.7 "Clifford"
2014 Stealth Evo 2850- "Woodstock"
2011 Toyota Tundra Rock Crawler TRD 5.7- "Clifford"
2013 Honda Accord Coupe V6 w/Track Pack- "Julia"
Just glad to get away