I would suggest: Please fly in an A340 first before you tell stories like "I've heard that...".
It's ok that you Boeing people hate the Airbus products, that shows the success of the planes. But you shouldn't talk bad about it just to express your dislike. I'm sure you guys have never flown on the A340, only on your magnificent sevens, so your conclusion is: Airbus is loud, rigid and so on. You know what? I can only laugh at you.
Now, NYC Int'l,
I know the A340, I've flown on Singapore's Celestar, and my impression was an extreme low cabin noice, it was almost too much quite for an aircraft. Additionally it was very comfortable.
But what was not impressing was the acceleration, that was weak. But ok, it is known that the A340 is no sportscar, the CFM engines just don't provide a lot of power.
Air France has equipped some of the A340s with personal TVs in Economy, so maybe you're lucky and can enjoy them.
Oh, by the way I've also flown the B777 and it's great too, very quiet and comfortable. But I wouldn't say there are big differences between both, the B777 and the A340.
Me & You & a Plane Named Blue...