My wife has been using the virgin mobile myfi for atleast a year now with great success. Granted when she goes to congested cities like downtown Detroit or Atlanta it lags but it still has great speed. We still pay 40.00 dollars for unlimited service as we are being grandfathered from these changes. As soon as we lapse in service we lose this feature but everything works like its supposed to with continuous speeds above 1.5mbps.
You are lucky to have it work at all. Here it got so slow that web pages wouldn't even open anymore so I didn't renew it. There's nothing I can do on my end to make it run slower or faster, I'm already getting a strong signal since all the carriers have antennas within 1-2 miles of my house. Since I'm a network admin. I could probably help them with their problems and speed it up but since I don't work there and can't get the keys to get in or the passwords there's nothing I can do for them except move on to something better.
Yep it's true I've been the network admin for the college district for 10 years. We have great internet service at work because I set it up and maintained it myself but can't get internet service at home since there aren't any honest companies that can provide it where I live.