Originally Posted by acf573
Unfortunately, it is somewhat of a hassle beyond that. They can confirm the upgrade (or waitlist) that way. But before your flight segment, they need to go to the airport or a United ticketing office to sign a blue authorization form. The only exception to this is if you and the other person have the same last name. This may or may not be a big deal depending on how far they're located from an airport (not sure if subcontracted stations can handle this sort of thing--you may want to confirm the details with UA first) and how soon your ORD-HKG leg on UA is.
This will work with certs, but I am not so sure about with miles. Might want to check with the UA forum on that one, but I believe miles can be used only for yourself, or somebody on the same itinerary.
As for the initial decision, go with LH F. You have laid out several very good reasons "for" and only one small one "against"--the miles. But the LH F terminal in itself is probably worth a premium of that many miles, and when you factor in the difference between LH F and UA F, I think it's the right choice. (and the suites really aren't that close together in UA F--you two will be happier in C
)