Data plans and performance
The T-Mobile Rocket 3.0 comes with four data plans: 10GB, 5GB, 2GB, or 200MB for $85, $50, $40, or $30 per month respectively. These are very low data caps because at full speed the Rocket 3.0 can burn through 10GB of data in just about an hour of heavy downloading. As with the T-Mobile 4G Mobile Hotspot, when the data cap is reached, you won't have to pay more for continuing usage. Instead, the modem's speed is throttled down to a very slow speed, equivalent to that of a GPRS (General Packet Radio Service) or EDGE connection, for the rest of the month.
For the time before the data cap has been reached, however, you're likely to be happy with the Rocket 3.0's performance. In our testing around the San Francisco Bay Area, the device turned in download speeds of between 1Mbps and 13Mbps. This is a huge fluctuation, but that's not unusual for a cellular data connection. In the end, we found the device typically managed around 6.7Mbps download and around 2.4Mbps upload. These are very fast speeds sufficient for almost any Internet-related uses, including streaming HD content.
Note that we weren't able to experience the double 4G speed that T-Mobile claims for the device, even in recommended locations in San Francisco, such as at Pier 39 or around Chinatown. This is rather disappointing but considering the low data caps it could be a good thing. It also doesn't mean the modem is unable to offer those speeds, as perhaps it can in other cities or at different times of day.
(Longer bars indicate better performance)
The T-Mobile Rocket 3.0 4G Laptop Stick didn't meet our expectations in regard to the double 4G speed T-Mobile claims, but still was very fast in our testing, on par with and sometimes even faster than other 4G devices we've reviewed. It would be an even better with an unlimited data plan, but it's still a good choice for anyone who travels with a laptop.