Get the one with the remote display...hands down easier overall. The EMS needs to be installed somewhere that is usually between the incoming line and the transfer switch (if you have generator power also) and if you don't, then it goes between the incoming line to the trailer and the breaker panel. It would be almost impossible to find a location to put the one that has the built in display, somewhere that you can see it AND mount the unit where it needs to be. The remote unit setup can be located wherever it needs to go, the the display mounted somewhere that is easy to see....it comes with like 25' of cable, so pretty easy to find a place to put the separate display and have the EMS mounted in the basement or behind a panel or wall.