Stadia, the new cloud-gaming platform from Google, can stream Destiny 2 to a TV, PC, or even a smartphone. That’s an impressive technical achievement, but it has a drawback: Stadia sucks down an incredible amount of data.

In our extensive testing, a Google Pixel 3a smartphone playing Destiny 2 over Wi-Fi consumed data at a rate of 10.2 gigabytes every hour. That’s enough to demolish most mobile data plans in 5 hours or less.

Even home Internet might run into issues. Comcast’s Xfinity data plans include 1TB of monthly data in many states. After that, users are charged $10 for each extra 50 gigabytes used, to a maximum of $200 extra per month. That could add up quickly if you do exceed the cap.

You’d have to play Stadia for 3.5 hours every day to blow through a terabyte of data. Most gamers won’t, but serious gamers could easily put in the time. A gamer averaging 5 hours a day would exceed Comcast’s data cap in 21 days. And that’s if the only data you use goes to Stadia, which is not the case for anyone.

Stadia’s data use is high even among streaming services. Netflix officially quotes HD streams at 3GB of data per hour, while UltraHD content can consume up to 7GB per hour. Stadia’s data use isn’t out of line with YouTube, however. Our testing finds that 4K streams of YouTube videos use a similar amount of data on the Pixel 3a.

In today’s world of 100GB game downloads, and 50GB patches, Stadia’s data use may not seem out of line. Gamers are frustratingly familiar with huge downloads that, at times, are mandatory to launch a game.

Stadia promises to fix that annoyance. There’s no initial download; you can simply launch any game you’ve purchased the moment you own it, and you never have to wait for a patch.

But, as our testing shows, that convenience translates to much higher data use over time, and you’ll pay for the convenience if you blow past the data bundled with your Internet plan.

Still not sure if Google Stadia is worth your time and money? Read our in-depth Google Stadia review.