Things have calmed down greatly -my YUL-EWR flight on AC yesterday was rather painless in terms of getting through the airport. And with the secondary searches going away altogether, it's business as usual again.

As far as customer service goes, I actually found AC to be quite flexible. On my outbound flights to Montreal, I was allowed to change to a better routing 2 days before departure on account of the then-major transborder disruptions, and when my EWR-YYZ-YUL trip got cancelled due to weather, I was moved over to a CO EWR-YUL flight with a minimum of fuss in accordance with IRROPS policies for Star Golds. And, I scored a bump ($200 CAD - AC EWR counter exchanged it for $192 USD voucher) on my YUL-YYZ flight yesterday, and was rebooked on an AC Jazz nonstop YUL-EWR.

But for the lack of elite mileage bonuses, I'd use AC as much as I use CO (or will use UA once we get access to E+).