Concierge services on UA International First Class is one of the few 'real' benefits and services to be appreciated, especially in Asia and Europe. I have had marvelously helpful assistance from them at LHR, CDG and NRT as well as HKG. When you have a special request, often concierges can put in your PNR or telex the port of your arrival.
Particularly helpful in making tight connections, I have discovered. I love those private-wagon/electric cart service at LHR and HKG.