Hi folks, I'm a T-Mobile customer but I'd like to buy an iPhone 7 on Sprint/Verizon model to have the CDMA capabilities -- T-Mobile is great worldwide, but in certain rural areas of the US it still roams on Verizon's old networks, which is critical for travel. How is it possible to buy a Sprint/Verizon model and use it on T-Mobile? I walked over to the Apple Store, and they said that if I buy a Sprint/Verizon phone, it will be locked to Sprint/Verizon in the US -- even if I pay full price upfront. Have any of you had success with this? Thank you!