The new program, called Binge On, allows T-Mobile (TMUS) customers to binge watch videos from 24 different service providers without any of it eating into your data plan. Go ahead, watch the entire season of Narcos on Netflix (NFLX) on your smartphone while sitting in the middle of a park. In addition to Netflix, Hulu, HBO GO, HBO Now, ESPN, and Sling TV are participating. (You can view a complete list here.)

New customers can sign up for Binge On starting Nov. 15. Existing customers are scheduled to receive it starting Nov. 19.

Unlimited streaming video on a mobile connection seems like a deal that’s too good to be true. So, what’s the catch? There’s always a catch.

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During the announcement, Legere explained the company has developed proprietary software to optimize the video stream which reduces the amount of data used, while providing “DVD-quality” streams.

According to the fine print, T-Mobile’s Binge On program will stream videos at 480p. This seemingly small detail could wind up being a big deal to its customers.

Most modern smartphones are equipped with high-definition screens, capable of displaying 720p or 1080p high-definition video. Legere assured those in attendance the streaming quality wouldn’t be an issue, reiterating that 480p video looks just fine on a smartphone’s screen.

To put Legere’s claim to the test, I opened the YouTube app on my iPhone 6S and set the stream quality to 480p. I watched video after video, and you know what? The quality wasn’t all that bad. Of course it wasn’t nearly as clear as high-definition video, but at the end of the day every single video was completely watchable.

I watched a highlight reel of NBA superstar Stephen Curry scoring 53 points in a game. The video’s lower quality was most evident when players were running down the court, or whenever there was a lot of quick movement. Outside of those minor gripes, the video looked okay. Not great, but okay.

Another video I watched was from technology reviewer Marques Brownlee, who also happens to shoot his videos in 4K. While I couldn’t watch the 4K version on my iPhone, his review of the Nexus 5X downgraded to 480p looked just fine. I didn’t feel like I was missing out on anything, and in fact, I barely noticed a difference when I rewatched the same video in high-definition (720p).

Without a question I would pick streaming low-resolution video over having to constantly monitor my data usage on AT&T.

It’s entirely possible T-Mobile’s method for downgrading the video could worsen the overall quality, but unless the video comes across as a pixelated mess, I think most users aren’t going to care about—or even notice—the lower video quality.

For those who refuse to watch a movie in 480p, T-Mobile will allow you to disable Binge On through its website. However, doing so also means streaming video will count against your data plan.

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