We just brought home about 12 bottles of wine from New Zealand as well. The wine shop sold us boxes (3-bottles each) and we put those inside our carry-ons. Wine is heavy - so do be sure you haven't overloaded your carry-ons. I can't imagine being able to bring a 12-bottle box as a carry-on - wouldn't it be too heavy and large for the overhead? Also, duty is not the only issue. You might do a search to see how much wine your state allows you to bring in.