T-Mobile says it has added more new postpaid customers than its rivals each quarter for several years running, and to keep that momentum going, the company is again trying to squash negative perceptions about its network’s reliability and coverage. T-Mobile is now offering free trials of its service in Atlanta, Georgia; Austin, Texas; and Boston, Massachusetts. The company made no mention of this new program during today’s Uncarrier event.

Unlike the nationwide Test Drive program that T-Mobile ran in 2014, where people could use an iPhone 5S that had T-Mobile service, this time, testers will get a portable Wi-Fi hot spot with a SIM inside. You’ll have to connect the device you’re testing to that to get a sense of T-Mobile’s network performance and scope of coverage. But you’re getting more flexibility in that you can use whatever phone you want with the hot spot, and you’re also getting more time. Test Drive was only a 7-day trial; this one lasts 30 days or until you hit 30GB of data — whichever comes first.

If you live in one of the three markets and sign up, T-Mobile will mail you the hot spot with two-day shipping. The free trial doesn’t cost anything or even require a temporary hold, at least according to the T-Mobile site that makes no mention of charges. The fine print only says that participants can expect to get emails about their free trial.

There’s no word on whether T-Mobile’s new free trial will expand to other regions. It’s a nice offer for people in these areas who have considered switching — perhaps for better customer service. But major cities have never really been the main holdup with T-Mobile’s service; it’s the suburbs and countryside that have, in the past, made service gaps between T-Mobile and Verizon / AT&T more pronounced.