Great airport.
Arrival -
Long long walk. We exited our United flight from SFO and headed toward immigration. There are posted signs every minute or so counting down to when you're finally down the ramp where you need to fill out a customs form. Plenty of greeters who will point you to what & where to go. On route our United flight attendant gave us wrong info - said no need to fill out a paper form as they've got electronic kiosks that takes the place of the paper form. Duh - you need to fill out the paper form; then feed it through the kiosk where it dispenses a copy. Hold on to the copy as you'll need it for customs.
First it's immigration; then it's customs.
Departure -
Even though our boarding pass stated TSA pre check, that only applies on domestic flights. We had to go through the normal line. On the conveyor belt - gotta take a plastic bin and put shoes, jackets, backpacks, and our carryon luggage. Actually took two bins. What I forgot to do was take out my liquids. So the security person opened my luggage to examine what liquids I had. That took a few extra minutes.
The US & Canada has an agreement. The Canadian airport is considered your point of entry back into the States. There are GOES kiosks there. If you're in the GOES program as we are, you can scan your passport; answer the typical questions, match your fingers, and head over to the GOES immigration line.
The airport is clean. It's airy. It seems new. Friendly greeters. Lots of folks to help point you to where you need to go. There's even an information kiosk staffed & they'll let you use the phone to make an outgoing call if you need a hotel pickup at one of the nearby hotels.