I bought the smaller version of the Always-On "on spec," hoping that it might just fit the Panasonic Lumix GF3 with the 14mm or 20mm lens. It didn't, so I ordered this larger version. It fits the camera + 20mm lens nicely and I am now a lot less worried about carrying the camera around in my jacket pocket. You have to adjust the wrap sideways from time to time, probably because the camera lens is off-centre on the camera body. The wrap is not that much wider than the standard sized one (around 15mm, but check for yourself), but it is about 5cm longer. The rubber platform that you screw to the bottom of the camera is the same size as the one on the standard Always-On - around 8cm wide, which means it is not too wide for the GF3.
The wrap will not fit the compact 14-42mm zoom lens that comes with some of the Panasonic kits. I don't know whether it will fit the new 14-45(?) X-zoom lens, but the wrap can be stretched a bit so it will probably fit something a bit larger than the 20mm lens.