The problem with highlighting minimal differences in service levels is you might actually build up expectations that one carrier is significantly better than the next one, and you might build up expectations that the flight is something to look forward to.
One carrier might have been better 20 years ago but it isn't the case today. So take the cheapest flight and if you don't enjoy it, and lets face it who does enjoy being in the back of a transatlantic plane, at least you know you paid the lowest price going.