There are many benefits to the electric fan, but IMO the best is that the mechanical fan is not constantly sucking HP thats sorely needed @ the rear wheels. Last week I drove from DC to harrisburg PA (120 mostly hiway miles) and turned on my fans once, at the end of the trip as I was parking it.
1980 Jeep Cherokee Laredo WT 360/727/208
1980 MBZ Euro 300D 4-speed manual - Oil Squeezer
1984 MBZ Euro 300D 5-speed manual - Oil Squeezer