想知道t-mobile Advantage Program到底能省多少，结果收到的email里面就是说：
Lower monthly rates with access to Unlimited Nationwide 4G Data
Savings extended to family members or authorized users on your account
Discounts on select phones and special promotions online, with a 30-day risk
-free return policy. Go here for return policy details.
Free standard shipping on purchased devices
Easy switching—even keep your same phone number
有没有人知道这个program到底有多少discount?
