I use it on I-16 between Macon, Georgia and Savannah, Georgia. Average speed is 75mph. I also use it on I-75 between Macon and Atlanta. Average speed of 65 mph. I use a USB760 modem and a netbook to mainly surf the web for maps or business websites. Sometimes make reservations for river cruises or hotels. Obviously I am not driving and am a passenger, so I can deal with the occasional dead zone or overloaded tower between Atlanta and Macon. The problem usually lasts only about 1 minute. There are 5 spots along I-75 I know the signal will fail for 30 to 90 seconds. I just wait until we are through them. If I get permission from the vehicle owner/driver to put a magnetic external antenna on the roof of the vehicle, the signal loss problem is significantly reduced. Usually I just refresh the browser to reload a partially loaded website. I do not try to watch video because it does not work well enough to be enjoyable. Maybe when LTE is fully deployed I will try video watching.