The short answer is yes.
Before giving you a longer answer, I want to give some context. I have flown over a million miles to twenty-eight different countries in the last ten years. [Edit: none of this travel was for work. Every ticket I purchased came out of my own pocket.] I mainly fly Lufthansa, British Airways, and Delta. I have also flown Emirates, Qatar Airways, Ethiopian Airlines, Icelander Air, and others. I mainly fly out of Seattle for my international flights.
The benefits of flying business class go far beyond having a lie flat seat.
The first benefit is that you usually earn more frequent flyer miles than passengers in economy for the same trip. You can rack up miles really fast when flying in the front of the plane. I now have several free international first-class trips at my disposal.
The second benefit is access to business lounges (or if you are flying first class, access to first class lounges like the Concord Room at Heathrow). International business class lounges almost always come with free showers. It is such a pleasure to be able to take a shower and change clothes after a ten-hour flight before I hop onto my next flight. Business class lounges also have free food which is way better than what you can buy in the main terminal. Finally, business class lounges let you know when your flight is actually boarding.
The third benefit is walking straight out of the lounge, down the concord, and onto your flight without breaking stride. No standing around the gate area hoping to get on the plane before all the overhead bins are gone.
The fourth benefit is what you can carry onto the plane. Almost all international carriers allow two carry-on pieces of luggage and a small backpack or purse. As a result, it's been years since I checked a piece of luggage.
The fifth benefit is overhead bins. Fewer people per square foot in the front means that you always have space for your carry-on luggage. I literally never have had an issue with overhead bin space in business class. I cannot say that about economy class.
The sixth benefit is eating when you want to eat. If you miss meal service in the back because you fell asleep, you usually don't get a second chance. Up front, you normally tell them when you want to eat. Plus, its better food and served with real china and flatware.
The seventh benefit is that business class is populated with professional travelers. No crying babies, no one clipping their toenails, and no one kicking the back of your seat. More importantly, everyone in business class lowers their window shades after takeoff to allow others to sleep. [Note: this is becoming less of an issue with newer airplanes. The latest Boeing 787's and Airbus A350's give control of the window shades to the flight crew. With one push of the button, all the windows go dark.]
The eighth benefit is the seat itself. There is nothing greater in the world than pushing a button to have your seat turn into a bed. Add a real blanket and real pillows and you are in Heaven. Seriously. NOTHING GREATER.
The ninth benefit is getting off the plane first. Lines at Immigration and Customs are often a breeze as a result.
The tenth benefit is that business class luggage is loaded last on international flights. As a result, your luggage comes off the carousel first.
The eleventh benefit is customer service. If your connecting flight is canceled, your airline takes care of business and first-class travelers before it gets to the people sitting in economy.
And finally, did I mention the seat that turns into a bed?