Although I have a different experience from PP's, I must say there seem to be a good reason for me to agree with him when he votes for Britannia.
Like many BA guys, I too, was placed in a holding pool.
For various reasons (incl. Recruitment freeze, bad luck, 911 etc...), I spent nearly 4 years swimming there.
Well, unlike BA, Britannia has kept me in the pool all these years and still offered me a position when things picked up again.
So in my eyes, that is a sign of a "Best airline to work for", specially when this is added to the benefits mentioned in PP's post.