I fly all the major US airlines regularly and AC once or twice a year. I used to enjoy AC and looked forward to flying them... and until a couple of years ago, considered them 2nd only to AA in domestic NA catering. But my how things have changed. AA has gone from first to worst among US airlines since DUI Dougie and his crew took over and trashed the place. And if
my recent AC LAX-YUL-LAX flights are an indication, AC has fallen off the cliff as well. On the other hand, UA has improved significantly after the BOD gave Jeff the boot. IMO, after B6 and VX, they now have the best domestic food of NA airlines.
I would rank domestic NA premium class service as follows:
1. JetBlue Mint
2. Virgin America
3. United
4. Delta
5. American
6. Air Canada and Alaska
Add in the inability for AC or Aeroplan to answer a phone call in a reasonable amount of time and other IT issues, and AC probably ranks lower than Spirit for overall experience.