I recently had wifi unavailable on a "wifi available" flight. Then, it woke up and came to. Happy, I paid for 2 hours worth. The connection lasted 4 minutes total, per the UA remaining time counter, stuck on 1 hour 56 minutes.
So . . . I really do hope the content is 100% local! The wifi is pretty shoddy right now on UA. Too bad . . . it's easy money for an airline that needs it!