I got to fly on one of the 747-123 that Braniff leased from American Airlines back to Hawaii in 1978. It just had an orange stripe replacing American's stripes on bare metal rather than the pumpkin livery. The inside was very nicely done. the coach sections had 9 abreast seating rather than the usual 10 so it was much more comfortable than Pan Am's 747-121. The meal service on the Hawaii flight was the same as a Braniff's normal first class meals on their 727s. My parents flew in the first class section on that flight, and their meals were better than many five star restaurants.
I like the upper deck, I rode on our old 747's up there a few times and in coach once on South African up top. Like a private club.