This was my first time arriving and departing Canada from Pearson Intl. (terminal 1) and I was impressed. Arriving on a Sunday evening and departing at a regular day of a regular week the Airport was specious with comfortable seats everywhere. It is sparkling clean and the employees are nice and helpful. It was very easy to find my way around and when I hesitated there was always an employee standing just near by to direct me.
I loved the big bright counters with the high white chairs where you can order food through an iped, pay at a station on your table, and brows the internet for free, while the iped updates you about your flight. Very comfy. The food selection was somehow limited (at least at the F gates) and that is why I did not give them five stars. There was one Starbucks that moved so slow I just gave up.
I never believed I'd say that about airport customs, but the USA customs here are the fastest and most pleasant customs I ever went through.