I do technically, but only in the strictest sense of the rules of the program. Using Next to purchase devices saves $25/mo per phone on our monthly Mobile Share Plan, which for us equates to $75/mo. So over the course of a year we save $900. But rather than pay for the phone in installments, I purchase the device on Next and then pay it in full the following month. And since the other two phones on the plan usually just use my hand-me-down devices
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, I'm only buying a single device per year at full retail--works out to hundreds less per year vs. the traditional 2 year contract with discounted phone pricing--and we're not locked into a contract.
You can use Next to pay the phone off in installments and trade it in after a set period of time (depending on the installment term you choose) but then you've basically leased the phone for half the full retail price.
I know Techarchy uses the program in that fashion so if he sees this, I'm sure he can offer additional insight from that perspective.