Pros: gas price is always 10c cheaper, that for me translates to 5-7 dollars per charge, since I have a 80km daily commute home need to charge every single week, if you do the math this is at least a $250 dollars per annum savings.
Cons: the reason I'm giving just 3 stars is because hours of operation are ridiculous and speed of the pumps are subpar for those, let's say ESSO stations. They need to figure out a faster way to start the process of pumping gas. This coupled with the few that get confused with managing the Costco card and the credit card.
So if you spend lots of money in gas, this is your best bet, you just need to find the best time to pump so lines are not that long.
(Me, I'm moving to an electric car as soon as possible!)