I could have flown the same route in about 1:10 however the ferry for two was the same price as flying for one, saved two nights hotel accommodation as each leg was overnight and was more reliable than going by air as flight cancellations and delays on the route were not unusual due to weather.
I was trying to give a comparison of 16 hours on a ship which was quite pleasant compared to 16 hours crammed sitting in an aircraft with limited movement which would have been miserable.
Different matter if you can afford first class on Emirates with your own suite and shower available, have space to move around and even a bar to sit and have a drink at.