You need deep pockets for any class on 787 with BA
It is used on routes where you pay premium just for the honor of flying direct like Austin and you are charged "direct flight" premium. For example LHR-Austin with one stop using any number of airlines is ~ 60% of the cost of BA direct routes. Same for others.
I really do not want to know what first class costs in this thing. Just economy is eye watering (and not worth the 2-2.5 hours saved on being able to skip a xfer).