. 7E7 is smaller
A350-800 = 245 seats 8,600 nm
7E7-8 = 217 seats 8,500 nm
A350-900 = 285 seats 7,500 nm
7E7-9 = 257 seats 8,300 nm
A350 is not the competitor of 7E7. They are on two distinct, but very closely positioned, market segments.
Because A350-800 and A350-900 are A330 on steroids, A350 will be a tough competitor of the current A330 and A340-300.
A350-900 = 285 seats 7,500 nm
A340-300 = 295 seats 7,400 nm
A350-900 will take benefit of new generation engines so it will burn much less fuel than A340-300.
A330 and A340-300 will simply be crushed by their younger sister A350.