Rob Pegoraro

Special for USA TODAY

Q. How do the new unlimited-data deals at Sprint and T-Mobile compare?

A. The rewritten all-you-can-browse offerings from the nation’s number-three and number-four wireless carriers have a couple of things in common: Both are cheaper than earlier unlimited plans at each firm, and neither quite qualifies as unlimited on closer inspection.

With Sprint’s Unlimited Freedom plan, available from Friday on, you’ll pay $60 a month--down from $75. You can still use your phone as a mobile hotspot, and the “tethering” allowance of 5 gigabytes exceeds the old plan’s 3 GB ceiling.

But you also have to accept “mobile-optimized” treatment of videos, music and online games. A note in smaller type explains that video will be limited to “480p+” resolution, or just above standard definition, while music gets a 500 kilobits-per-second speed limit and gaming is capped at 2 megabits per second.

The tradeoff with video may be fine; on a phone’s screen at a handheld viewing distance, you may not notice any difference. The music limit certainly seems okay, considering that Spotify’s highest-quality service maxes out at 320 kbps.

But gamers may not be pleased. Sprint defines “premium” gaming as an 8 mbps proposition, spokeswoman Michelle Leff Mermelstein wrote in an e-mail, so getting knocked back to 1.5 megs could hurt.

The new $70 T-Mobile One plan ($75 if you don’t enable automatic payments) replaces today’s $95 unlimited plan starting Sept. 6 and requires giving up more. The big one is tethering, which now costs $15 a month extra for a 5 GB allowance unless you can live with tethering at only 2G speeds. (No, you can’t.)

T-Mobile One also imposes the same video “optimization” of that carrier’s BingeOn option. As USA TODAY’s Jefferson Graham demonstrated in a video here in January, services that haven’t adapted their streams for this can stutter and freeze during playback. Opting for high-definition video will add $25 a month.

The language in T-Mobile’s announcement of the new plan—the "T-Mobile Goes All In on Unlimited” headline, the "T-Mobile ends the era of the rate plan with one simple offer” declaration--seemed to say the carrier would stop offering its lower-usage plans, but that’s not so.

As T-Mobile PR confirmed Friday, those offerings--2 GB for $50, 6 GB for $65, 10 GB for $80--will remain available. They all include tethering, the option to enjoy unlimited music and video streaming via BingeOn or opt out of that for free, and “Data Stash,” the ability to sock away unused data for use over the next year.

(Disclosure: I’m a T-Mobile subscriber myself, and Data Stash has allowed me to keep an older 3 GB plan that would otherwise run out some months.)

Sprint, too, continues to sell its “Better Choice” plans: 1 GB for $40, 3 GB for $50, 6 GB for $65, and so on up to 40 GB for $120.

My verdict: Ignore the T-Mobile unlimited deal unless you have an unlimited or 10 GB plan now and yet never use your phone as a mobile hotspot. Current plans already include unlimited BingeOn video streaming, zeroing out what’s usually the biggest consumer of bandwidth; as analyst Roger Entner noted on the company’s conference call Thursday, they’re “de facto unlimited.”

Sprint, however, has come up with a stronger offer, in part because its older plans don’t provide unlimited video streaming. If you have today’s unlimited plan or a Better Choice plan of 8 GB or higher, Unlimited Freedom should be a good upgrade unless you play online games frequently that would suffer from the new “optimization” or you appreciate watching streaming video in HD.

Remember, also, that most people don’t use that much bandwidth. At Verizon--which still doesn’t have an unlimited plan—subscribers averaged 2.7 GB of data in April.

Rob Pegoraro is a tech writer based out of Washington, D.C. To submit a tech question, e-mail Rob at rob@robpegoraro.com. Follow him on Twitter at twitter.com/robpegoraro.