Im a current T-Mobile user still using a plan I got back in 2004, so all these data plan things are new to me... I've decided to go with AT&T so that I can read an email or look something up while talking on the phone. If I choose the 1GB data plan with them, and I find out that its not enough for my usage, can I move up to the 4GB without any penalties? Conversely if I go with 4GB and notice I never go over 1GB, can i downgrade without penalty? I tried calling my local at&t store but they seem pretty slammed right now and clueless about all my questions.