I'm being forced to switch from UA to DL and AA, due to UA's inability to hold onto their gov contracts (small wonder). However, I flew DL on most of a HNL NRT BKK RT last April and was pleased by some things and not-so pleased by others. Mostly it was a bunch of trade-offs but the cabins were cleaner, I found the premium seats more accessible/easy to purchase, and the SkyLounges were almost as good as ANA's. UA Club sucks anyway.

The most conspicuous part was irrops; about 90 minutes after leaving HNL on time, one of the FAs suffered a really nasty knee injury, so back to HNL we went. This essentially meant a 4-hour delay getting to NRT, so our connections were toast.

Now, I go through NRT at least 4 times a year, and it may just have been that I like NRT or that it was a Japanese airport and their standards of customer service are just that good, but contrast the following experience to your average blown domestic connection:

-Disembarking we saw a herd of smiling airport staff with printed (not hand-scrawled) signs above their heads, with the city and flight number of our then dead connections.
-"Please wait here. Thank you!" (again, smiles)
-After all pax going to a particular city were gathered, we were escorted (not shooed away) to the immigration desk for the fastest immigration check I've ever had. Our escort even guided us in filling out the forms, darn near did it for us.
-We were handed a new boarding pass and a bus ticket for HND. Short wait and we were off to HND. They automatically rerouted the bags by the way.
-Once at HND we were guided to the correct terminal and quickly checked in and off through customs, etc.
-I was rebooked by DL on NH, and since I'm *G, off to the ANA lounge I went with plenty of time for a shower, snacks, and drinks.

Got into BKK 5 hours late, but the way DL handled everything in NRT just blew my mind.