Earlier this week, Sprint’s new CEO Marcelo Claure tried to take a swing at its bigger and/or faster competition by announcing a shared data plan that gives you a ton of data… on a network that’s currently so slow you’ll never get to use it all. Now Claure and company are trying again, offering an unlimited data plan that’s cheaper than the competition but probably won’t win over savvy data devourers.

Starting tomorrow, Sprint will offer a plan with unlimited talk, text and data for just $60/month. That’s $20 less than a comparable plan offered by T-Mobile. Neither AT&T nor Verizon offer unlimited plans anymore.

Of course, there is a hitch — in order to qualify for the plan, you need to either own your phone outright or purchase it through Sprint’s Easy Pay installment plan. This means that Sprint customers who are currently under contract with Sprint will either have to wait until they are upgrade-eligible or pay a fee to move that eligibility date up.

The other hitch is that Sprint’s LTE network is achingly slow. Recent tests show that download and streaming speeds on Sprint are far behind all of its competition, including the smaller T-Mobile.

Oddly enough, the ideal customer for Sprint’s unlimited plan isn’t someone who wants to use an enormous amount of mobile data. Until Sprint beefs up its LTE network to allow for competitive download speeds, data hogs will likely just be frustrated. Instead, the only people who could see any value from the plan are bargain-hunters who use a moderate amount of data, mostly in the form of browsing the web and e-mailing.

But even for those people, some of the competition have similar options that don’t have unlimited data, but offer enough data for most consumes, and on much faster networks. For example, AT&T offers individual users a $65 plan with 2GB of data and unlimited talk/text. And T-Mobile’s unlimited plan might cost you $80, but the company offers a 3GB/month plan for $60. Both companies have 1GB plans for $50, but that might be too little data for some people.

This is why we always advise people to look at their actual monthly data usage to see if they are paying for too much. A lot of people grossly overestimate the amount of wireless data they consume every month because they don’t always differentiate between data coming over an LTE network and data coming over the WiFi networks in their homes and offices.

If you’re regularly using less than 2GB/month of data, there’s really no reason to switch to an unlimited plan when you can save money with a capped plan. Just make sure to keep an eye on your behavior to prevent going over that limit, because you could face costly fees.

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