You'll breeze thru Customs
I've been there 3 times for work, and each time I've just walked thru in less than 5 seconds. The line for immigration has been less than 5 minutes. The train from the airport to downtown is fairly new, and highly recommended. I'd say the highlight of the town is the lake and the surrounding area. Definitely worth a stroll. Can the public still get in to the UN? Security procedures have changed there. tls