The only advantage a 787 has over the A330 or 77W is speed. Its marginal but I think about 40mph faster.
We flew a TOM one to Orlando Sandford last summer and we slowly drifted past a Delta A330 AA 763 and a TCX A330.
Probably saved us 20 mins on a 9hr flt over other twins.
The windows are larger too, so slightly better view if in a window seat.
Other than that agree with LAX.
Not that Im complaining on BHX getting 8 Qatar 787s a week from next year
Nigel