Best US airport for whisky?

My main advice is to make sure you don't get into a situation where you have to go through security with a bottle purchased previously at an airport. Also, some airports have DF-only stores and you can only visit them if you're leaving the country so it may be only on your last airport in the US that you can shop.

That said, I was impressed with the SF airport DF in 2016 coming back from China. I picked up a rare Booker's there if I recall. Rare because it was 700 cc.

@RikS As Nozinan stated it could be a challenge if you need to through security again. However, not all is lost. I purchased a carry on US duty free and the shop put a special tag on the bag. The bag was then delivered to the secure side and I picked it up at the gate. As long as the tag is not tampered with you shouldn't have any problems going through additional security if that is a requirement. Most of the time when I'm switching planes I'm already on the secure side and it wasn't a requirement to go through security again.