The biggest difference is the price, on most international flights, the price for 1st class is usually about double the price for a business class flight, and business class is usually about 3-5 times more than an economy class flight. Most of the better airlines have full-flat beds in business class, you will get amenity kits and better food and alcohol selection than economy. Plus you will probably have a stewardess to passenger ratio of about 8-10 to 1 as oppossed to economy at 40-50 to 1. You will get lounge access, priority check-in ,priority baggage handling and priority boarding. I've flown 1st class on Cathay Pacific, what you will get is champagne and an appetizer when you board the flight, you will get down comforters and pillows, a good sized bed, large screen personal tv, Shanghai-Tang pajamas, caviar, personalized meals, your own individual "compartment," cooked to order snacks, a private 1st class lounge before you fly and on and on. On some of the better airlines 1st class is truly 1st class in every way, Is it worth the price, I'd say no. But if you don't mind paying the price, it's the only way to fly. Business class is normally just fine, you will have more than enough room, good food and drink, as well as excellent service. I hope I've answered your question.