Heading home from a trip to Vancouver, where I had the chance to see how Compass works out there. I purchased a regular, reloadable card from a fare vending machine at YVR and loaded it up with $20 in funds. They charge the same $6 for the card, but if you return it, you get that back.
I also created an account on Compasscard.ca to see how that compares.
The tap on and off system is nice, but causes a few line ups here and there during rush periods. That said, their gates work well and I saw a grand total of zero that were out of service across the five or six stations I visited. Bus trips are tap on only, but I didn't ride a bus while I was there.
They run a 2-hour transfer system which works well. The displays on the turnstyles tell you your balance whenever they deduct from it. Otherwise you see just a check mark.
It appears that you can go into the negative. I saw a few people with negative balances of less than a buck or two. There are also exit fare machines in the fare paid area for those who need to top up to get off the system.
Lastly, they also have single use cards - paper with RFID embedded. I used one of those to get from downtown to the start of the marathon (provided in our race kit). You needed to remember to keep the card because you needed it to tap out of the station as well. They have a two zone system there, plus an add-fare for trips from YVR.
All in all, it was very familiar to anyone who uses Presto, but overall it seemed to be smoother and easier to understand. The website was similar and reloading was easy online or at a machine. All Skytrain and Canada Line stations have multiple fare vending machines in the non-fare paid area where you can get reloadable cards, paper cards or where you can load up your card. The machines were far superior to the ones here.