You still should install a 50 surge protector. I did the hardwired one in zoo/dungeon.
This is the one I installed.
https://www.amazon.com/Progressive-Industries-Hardwired-Electrical-Protection/dp/B003AN1UA8/ref=pd_cp_263_1?_encoding=UTF8&pd_rd_i=B003AN1UA8&pd_rd_r=93f8e1a6-5cfe-11e8-85e9-dbae31ccb6d1&pd_rd_w=uoLlK&pd_rd_wg=18Wss&pf_rd_i=desktop-dp-sims&pf_rd_m=ATVPDKIKX0DER&pf_rd_p=80460301815383741&pf_rd_r=5DX7RV2E8K8FBWWDXWHK&pf_rd_s=desktop-dp-sims&pf_rd_t=40701&psc=1&refRID=5DX7RV2E8K8FBWWDXWHKWhile on a 50 amp outlet, if you loose neutral you burn up all your AC items with 240V across them. I did the hardwired one because it protects me from a problem with the powered cord reel for the shore power cable. And it is not going to grow legs.
I would also note that while powering the trailer for dry camping with our Honda eu2000i generator, I have to put a male cord cap with neutral and ground bused together in the generator second outlet for the surge protector switch the power on.