I’m very happy with China Southern (CZ). Hard product on long haul from US and Canada is very good (787....2-2-2) and superb (777-300 and A380...1-2-1). I cannot comment on Asian food options, but western range from good to excellent. FA are very attentive and put most legacy carriers to shame. I’ve never experienced any noise...J cabins are very quiet. You do need to remember that they are not American, so there are cultural differences (process of ordering meals, security officers on board..,and there is no meeting of the minds between China and the USA on the concept of ice in drinks!!). As for smoking from the cockpit...not on any of my flights. I am very suspicious of people who claim to smell it...on most long haul aircraft there is a galley and first class as a buffer (I’ve also flown FC and never smelt any). You can fly CZ with confidence. One point...most CZ flights from the US fly into Guangzhou (SFO may be an exception...WUH?), it would be unusual to fly to HKG...it’s so close you’d be better to train! Complimentary hotel if your lay over is 8+ hours.