Ive never had any real issue with AC. Most of their flights are on time, their planes are clean and no issues at the airports. Ive been on may airlines and AC is still one of the top ranked airlines in the world. 
Westjet is fun (much like Southwest airlines in the US), but they dont fly where I need to go on most occasions without flipping in airports, and I prefer to fly direct. WJ is also becoming the more expensive of the two major Canadian carriers.
Im sure the CEOs of WJ pull down a pretty hefty paycheck as well....
Gregg Saretsky CEO 2.6M in Comp.
Bloomberg numbers