1) not sure when you last flew CX. They changed J headphones a few years back and they're definitely better than the ones from 5+ years ago, but still your own will be better.

1a) not really sure how detailed we're supposed to get on headphone reviews before we're OT, I could go for a while...I'll just say I own both of the models you describe and they're both fine. Just review Amazon that will be much better. Bose definitely has best noise cancelling, although the audio quality kinda sucks if you're really into 'phones. So it depends what you'd use them for. If riding on planes is #1 concern, go with Bose. If high quality sound is first and plane rides are a small part of your use case, generally Bose isn't what you choose once you decide you want to pay up for good stuff. I currently rotate my plane rides between two Bose over ear sets and ear buds. (I like the ear buds if I'm on a sleeping flight, I sleep on my side and put one in my ear thats exposed with some music when I go to sleep).I used to bring my Sennheisers on board the plane but everything is lost once the plane noise gets going and that's where Bose really shines, on the noise cancelling aspect.

2) The A350 doesn't need an adapter your assumption is correct. However, you need to be sure if you're flying back on a different plane (SFO will get each of 77G, 77H and 35G daily starting in a few days). Most 77Ws still require a two pronged adapter. CX is refurbing the AVOD equipment on all 77Ws but the process just started, and I'm not even sure if the jacks will change or not as part of this. Either way you're far more likely to get an unfurbed 77W what requires the two prong adapter. They do not have them on board.

Enjoy your flight. Btw, CX WiFi on the A350 is excellent compared to other TPAC experiences....and CX is the only non-mainland Chinese airline I know whose wifi functions over China.
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