The 3G version of the Ipad is a few millimeters longer and a few millimeters wider that the Wi-fi version. It is also .1 pounds heavier. In addition, it has the black bar antennae on the back. Will the 3G require different size cases to account for its slightly larger size? And is it likely that the antennae area will need to be "uncovered" for proper 3G reception? I would like to order a case in advance of my 3G but I am thinking that a lot of these cases will not fit and may interefere with reception. Thoughts?