OK, i am leaning towards the Emcotec Mini 6 unit. The next question i have is about the switch and battery setup. Do the batteries plug directly into the unit or do they plug into a switch and then the switch plugs into the unit? I have never owned any of these and i am just trying to learn as much about it before i buy. The ease of installation is important because of the tight spaces in the airplane! Any help would be appreciated...