If you have a choice from the get go, I would go electric! With that said.....having towed with both, a surge system setup properly works well. I like a couple of others, feel it is easier to get an electric setup to work, along with generally speaking, better working at the end of the day. If it were a trailer with surge, vs one with out, I would go surge. OR< buy the one with out electric brakes, assuming the axel has the correct backing plate to instal a set of electric drums, rim diam is big enough etc. For $250 and 4-6 hrs, you have electric brakes installed.
Marty