I'm moving to an almost deserted island for 9 months with no internet service. T-Mobile cell phone reception is "best". I wanted to buy an original iphone and tether it to my macbook. 1. Which t-mobile data plan should I add on? 2. Is "unlimited" really unlimited? Upon tethering, I don't wanna end up getting a huge bill at the end of the month for excessive use. Will they end up capping my bandwith with the tethering? Any help is much appreciated!