IS ONE OR THE OTHER A BETTER PERFORMER AND DOES IT JUSTIFY THE COST AND EASE OF INSTALLATION?
If you have mostly wall to wall carpeting and it is deep, then you may want to spend the extra money on the 120 volt powered. You dont have to make that decision now during the rough in. There are ones that have a long tail which should reach a nearby receptacle. The air driven ones work fine provided the machine is big enough and isn't too far from the inlets. By the way where are you and what kind of price are you looking at?