My experience:
I paid $500 in extra fees in order to fly first class on what I knew would be a terribly uncomfortable flight. The plane we flew on, though, actually had no first class service. We were seated in the first row of the plane, but otherwise saw no difference in service or amenities than a typical economy fare.
I complained by phone to Aeroplan after my flight, explaining that we were not satisfied with what he had paid for. The customer service manager (I had escalated my complaint), a woman by the name of Carol, told me, and I quote word-for-word: "We're not going to do anything for you, sir."
I subsequently wrote a letter of complaint to Aeroplan's head office, explaining that my initial complaint was actually nothing compared to my shock at the horrible treatment I received from Carol, a customer service manager. I have never received even a form letter in reply to my complaint.