We flew the Irish national airline, Aer Lingus, from London to Dublin in May 07.
Our first impression of the airline was very good. The check-in was through a kiosk and hence we got our boarding passes quite smoothly, even before the check-in counter opened. Aer Lingus also allows passengers to select seats beforehand - unlike other no-frills airlines - who have free seating.
As a result, the check-in too was quick. No luggage wieght problems.
At the boarding gate(not the airline door), the staff was quite pleasant - which does not happen with most low cost airlines.
On boarding the aircraft, we found that the seats were comfortable - there was ample leg space, some accessories were present, and no cost-cutting had happened there.
They had ample snacks on board, and the air-hostesses seemed eager to help with anything.
Overall, a pleasant experience. I recommend you fly Aer Lingus at least once.