There is a ton of variables that can effect RF range. Actually I would guess that RF range is one of... if not the most common... reason for an X10 post. I wouldn't expect that to change with the addition of the AirPad. Since WiFi also uses the old 2.4 GHz camera frequency that X10 used... there might even be a little conflit there.
We should consider a sticky of WiFi (2.4 GHz) devices that could be overlooked when tracking down a minor reception problem. Devices like a BlueTooth headset,... or a cellphone looking for a headset, wireless devices like keyboards and mouses(?)... mice(?), a video game unit (my Wii connects via WiFi), many baby monitors (and intercoms) use 2.4... some are even digitally secure. I have read that some appliances supposedly connect to the manufacture via Wifi and the Web for updates and checkups (although I've never actually seen that).
Then... when we consider the things in a home that can block or absorb RF signals like metal lath (under plaster or stucco), large metal objects like metal doors, refrigerators, metal file cabinets, or even a bad CFL, and so on and so forth.........
I am sure the AirPads reception is fine.