Hi guys, I am deciding between buying a Straight Talk iphone 5 refurbished -Works on verizon- (contract free and 1 year warranty)for $400 or an unlocked iPhone 5S from the Apple store. With either iPhone, I am planning to use the AT&T network on Straight Talk. However, the iPhone 5 will not have LTE speeds as the Straight Talk iPhone 5 is not compatible with the AT&T LTE network. having said that, which one would you buy? Is there a huge difference in speed between 4G and LTE? Would you pay $250 more to upgrade? I am tempted to buy the 5S at the Apple store, but I need to buy two phones and that means a difference of over $500...ouch...please give me your input. Thanks.