SirMS

In shorter worlds, around 15 years. In R1, I'm thinking 20-30 years.

I use 14/66/375, 72% legroom, a little heavy on F but it gets the job done

I always start in a new country and switch up the plane types. I've only played with a US airline once, my first airline. Inevitably, when expansion starts to slow, I'll get bored and let the idle planes stack up, but then I'll get the urge a few days later to come back and keep it going. And there is always fleet renewal and updating to look forward to. 

i've read from other threads that A340 is better than A330 considering thrust or something even though it has 4 engines.. i forgot. But is it possible that fuel consumption is not only comes from fuel flow?

The fuel flow given is the plane's total fuel consumption, not per engine. The A340 has lower fuel flow in-game because of some quirk in the way it's calculated, so it's more efficient than the A330.

Low fuel flow is better.