T-Mobile hasn't quite been as UnCarrier as some would like. Despite the network's turn toward overage-free service, there's still occasional chances that you'll pay extra for heavy use -- especially if you're on a grandfathered plan. That won't be a problem for long, though, as the carrier will soon eliminate overage fees across the board. You shouldn't be seeing any rude surprises on your bill from June onward. The move won't deliver huge savings unless you regularly pay surcharges -- and you'll still have to deal with throttling -- but it's good to have some reassurance that your costs won't get out of control in the future.