there are minor differences between the J seats on the 77W vs the A330 but not big enough to make me choose one over the other. They are 95% common imo.

the CX 77W J seats are identical to the AA 77W seats though i think (from the ONE time ive flown both lol) so if i had to choose between those id go with CX just for slightly improved catering

but to mirror everyone else here, definitely US 330 J seat > AA 772 J seat (pre-refurbishment), but even after refurbishment i dont think the difference is big enough to make me choose one or the other.

Then again im biased towards US so... lol