Since there's no single-carrier nonstop, your airline choice is really a choice of connection hub and cabin hardware. United's Polaris product connects through Newark's home hub advantages plus a change in Frankfurt or Munich, with the lie-flat 1-2-1 pod and Saks Fifth Avenue bedding that's become the U.S. benchmark. Lufthansa's newer Allegris suites, also routing through Frankfurt or Munich, add a sliding door and more personal space than the older Lufthansa business product — if you can get booked into the new configuration, it's worth seeking out. SAS routes through Copenhagen with a clean, Nordic-designed lie-flat seat and a genuinely good sustainable-focused menu. Turkish Airlines funnels through Istanbul, which adds flight time but comes with DO&CO catering that's consistently rated among the best in business class, plus lounge access that's practically a destination in itself. TAP Air Portugal via Lisbon and Austrian via Vienna are the value plays — Austrian's 2-2-2 configuration is angled rather than fully flat, so it's the one cabin here I'd skip if lie-flat sleep matters to you. LOT Polish via Warsaw is a solid budget-lie-flat option and interesting if you want a stopover in Central Europe.