1. For carry-on items, you need to check with the TSA website. For flights going into USA, there will be 2 security checking in HK airport. One checks for general airport security. Another check for flights that is going to USA before you board the plane. (Which I hate it a lot, I cannot even buy the tax free Alcohol from HK airport. Anyway, it always you to bring small amount of liquid. I remember it was 3oz... check TSA website for detail.
2. If you use CX or CO, I remember the flight was around 16hrs for non-stop direct flight. Both JFK and NWK are famous for delay, so no surprise if you stick on plane a little bit longer. The meal is FREE... I remember there is a meal (dinner format) after it left HK, then a snack, then another meal (breakfast format) before you land. p.S> I love to bring an empty bottle to the plane, and then keeping for water for me after I wake up. Asking for flight attender could take time, usually it is very dry after wake up.
3. Buy your travelling plug in HK. US is expensive for this. It depends on your hotel. Some hotel may have 220v and International plug availabe. But just don't count on it. In New York, you can buy this travelling plug at home depot or best buy (in case you forgot, and need one. There is a Home Depot at 23 street between 5/6 ave) US's voltage is 110v, and plug look like | | . I know HK plug looks like / \.
4. $300 sounds a little bit too few. Suggest you to bring a little more just in case. Well... if you use credit card, it may be fine. But credit card may charge for additional International charge. Check it with your issuer before you use. There is an exchange store around 33 street between 5ave and 6 ave under Empire State building... the rate is kind of sux...
