I have owned/used over a dozen datacards over the years, and by far this Sprint Overdrive was the biggest turd I ever wasted money on. I could not wait until my anniversary date to get the upgrade credit and get the 250U.
The thing overheated ALL the time, to the point I would hang it in front of the AC vent to keep it cooled down, it would lock up all the time, and require a battery pull to reset. Would refuse to switch over to 4G when it was available, you had to force it in to 4G only, and then it wouldn't switch towers automatically without you having to disconnect/reconnect. Add to that the lack of antenna ports too. I can't recommend the Sprint Overdrive to anyone based on my experience with it over the last year or so.