Hey guys, I am torn between the iPad 2 64GB 3G and the iPad 2 64GB Wifi models. Yes, there is a $130 difference. For those with the iPad 3G model, I understand it has a GPS chip in it too. Is there any apps that is worth it alone for the GPS chip? (I know navigon supports the iPad) Also, I have an iPhone 4 with unlimited data. Could I use the SIM card in the iPad 2 if I just wanted to use it for the unlimited data? For the people who bought the iPad 3G and also have an iPhone, what was your justification on spending the $130 extra for the 3G version besides the GPS? Thanks!!