Basically, I'm planning on getting a data plan (because I don't actually have data), and my parents want to save money and get 2.5GBs. According to the data calculator thing on their site, I use 2GB (conservatively). I also heard that if you go over your monthly limit, they don't charge you, but rather, slow your connection down, but them being a giant corporation, I know theres fine print somewhere.

Anyone here use T-Mobile, and gone over their limit for the data plan? Did they make you pay extra charges? Also, if you did go over your monthly limit, how slow did it get?