Buying unlocked will save you money over two years because T-Mobile will give you a discounted monthly rate. I do it this way. Also, if you are considering a v

Buying unlocked will save you money over two years because T-Mobile will give you a discounted monthly rate. I do it this way. Also, if you are considering a variety of T-Mobile phones, then you can buy them and return them within 15 or 30 days. For example in the past season I've bought the Samsung Galaxy S, the Google G2, the HTC MyTouch 4G, and will buy the Nexus S. FWIW, T-Mobile has been great for me. The network is significantly better than ATT in San Francisco. Also, the customer service people are head and shoulders above the other wireless providers. They have taught me how to tether in Linux, how to root a phone, and were especially helpful diagnosing a GPS chip issue with me.