New unlimited data plans: Should you bite?

This post comes from Kelli B. Grant at partner site SmartMoney.

What would you do for unlimited smartphone data? Smaller carriers are betting consumers will ditch their current providers. But experts say doing so might not be such a smart idea.

The nation's fourth- and fifth-largest carriers, T-Mobile and MetroPCS, announced changes to their unlimited data offerings this week. MetroPCS will temporarily cut prices for its unlimited talk, text and data plan from $70 a month to $55, while, as of Sept. 5, T-Mobile will reintroduce unlimited data plans. (Currently, T-Mobile subscribers can buy an unlimited plan for $20 to $30 per month, but they get kicked to a slower connection after they surpass 2GB of usage each month. Those who sign up for the new plan won't have that limit.)

Carriers are hoping to attract new customers as data use increases and other providers cut their plan limits, says Andrew Eisner, director of content for Retrevo.com. "All the cool things smartphones do tend to take up a lot of data," he says. (Post continues below.)

AT&T and Verizon both have eliminated their unlimited plans for new customers, and as we've previously reported, they have also taken steps in recent months to reduce the number of users who are hanging on to the old unlimited offerings. Meanwhile, Sprint -- the only other big carrier to offer unlimited data plans -- has cited the plans as key to drawing in new customers.

But unlimited data may not be worth pursuing. "Changing providers is like refinancing your house," says technology consultant Alex Goldfayn. "It's that complex, and not something people take on lightly." Before switching, gauge signal quality and connection speed in your area. Early-termination fees are another consideration: Unless you're at the end of a contract, fees for leaving can top $350, depending on your phone and how many months you have left.

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Still want to switch? Consider waiting until at least early September, Goldfayn says. That's when Apple is likely to introduce a new iPhone, and whether T-Mobile or MetroPCS gets to sell it could make these new unlimited offerings more or less attractive.

Either way, experts say consumers shouldn't count on unlimited data for an unlimited time. "It's only going to get more restricted," Eisner says. "Carriers are afraid of overloading their infrastructure with data-hungry applications."

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