I have a phone that I am almost certain requires a data plan, the Motorola Droid 3. It is fantastic but as I said, I am almost certain it requires a data plan. If you are looking for a keyboard one of my friends has an LG but it does random restarts and has its share of bugs. Personally if I were you and your current phone works fine I wouldn't bother upgrading unless you were going for a smart phone with a data plan. Do you really need a full keyboard to send text messages? If someone is selling their used phone it is probably because they do not want that phone. If they don't want it, you probably don't either. If you do get a phone, get a new one so you can get a warranty, otherwise you are taking on high risk.