Generally, domestic models (brand names like Telsda, Lenovo, and CECT with a couple of exceptions somewhere) don't have 1900 or 850, so avoid those, no matter how good they look to you. International brands (like Motorola, NEC, and Panasonic) are mostly tri-band. Also, China may be your only place where you can pick up an unlocked NEC phone, so if you want one, this is the place to get one.