If it comes to spending an extra £20 - £40 to fly with Eastern I'd do it every time.
The major difference between, in this example Flybe, but it could be any other airline, and flying with Eastern is the superior customer service and excellent reliability offered by T3.
It knocks the spots off all the other regional airlines, it's rare that anything but the weather stops Eastern from operating on time and the service is always impeccable.
I know that someone will come up with an example of their tardiness which happened on a wet Wednesday in 2006, but I speak as an aviation professional who flys regularly on with both airlines and I have absolutely no axe to grind.