The Pearson Airport has a few things going for it and a lot of flaws.
The bad
1) The US Customs area and departure gates for US flights are awful. No amenities, awful wait times and generally an unpleasant experience.
2) Parking is outrageous. There is no cell phone lot (spot the folks PARKED on the 409 waiting!). Even a short term pickup will cost you 6-10 dollars. Long term parking is something like $28 dollars a day (insane!).
The good
1) The International area in Terminal 3 and Domestic area and terminal 1 are clean, modern and efficient. It seems like cross border travel to the US is generally what gets a boot.