My longest flight leg was SKG-ZRH-JFK with Crossair MD80 and Swissair MD-11. Eventhough I was traveling Y, the service was great.
Recently I traveled JFK-LHR (and vv) via Reykjavik (Keflavik-KEF) with Icelandair. Eventhough the 757's were a bit cramped, it was a great flight, the service was fine,the food was good! the movies recent, the drinks free
KEF airport is small, cosy, and clean we arrived on-time, and above all, it was cheap