When it's working, my MiFi 4510L is a wonderful device. The problem is that at least daily the device will just outright hang in use. When it does, everything just locks solid until the device drops the WiFi connection. The only fix is to remove the battery of the MiFi, reinstall it, and then power it back up.
The MiFi has over 9000 different version numbers, so it's hard to tell which one is significant, but the Modem FW version is 2.16.7.
What's wrong with the **bleep** thing?