My vote goes to the Inverness based FlyBE team- all friendly, caring and courteous individulas.
A close second would be British Airways,-followed by Cathay, Lufthansa, VLM, Easyjet, Germanwings, Loganair and Thomson.
Worst experiences I have had would be with TAP Air Portugal and Iberia whose CC unfortunatly didnt reflect the normally genuine hospitable nature of their respective nations on the occassions I have flown with them; cant say I've ever been impressed by Virgin either sadly.