Interesting. I had heard that the -400 could operate into LGA but wasn’t sure if it ever did. I fly for the “other” -400 operator and we use ours (used, I guess  :'( ) on routes to Europe and South America that needed more capacity than the -300 but didn’t necessitate a 777 or 787. I was fortunate enough to fly EWR-MUC on IOE and it was a great ride. Since the -400 pays more than the -300 at my airline, that was my only trip with it. Sadly they’re all or mostly all in Roswell, NM right now. Though I will get a day in the -400 sim next month when I go to training.  :)