I went outside with both iPads (1 Wifi only, one Wifi/3G) yesterday and wandered around in and out of the extreme edge of my Wifi signal for a couple of hours, BTW this is 20 miles from any 3G coverage. As far as I can tell, with only my pair of iPads, it's a toss up. Both were able to connect within a few feet of each other & connections were dropped at almost the identical distances as well. I found one spot the Wifi only iPad connected and held the signal, although both showed one bar of coverage, where the 3G model connected then dropped off but could not duplicate this event thereafter. As a sidebar I also took my iPhone, and while my iPhone almost always shows 1 or 2 more bars of Wifi coverage than my iPads in any given spot inside the house, the iPhone consistently lost the Wifi signal sooner than either iPad. These are my admittedly unscientific findings on one occasion yesterday evening. Take it for what it is worth.