I have had several shocking moments with the credit card. You have to read the small print. And you have to pay it off to the dime every month. I had a balance of $17,000ish in a high spending month (I use it for work), and cash flow was low but I made sure that I paid $15,000 (worked hard at this) by the due date, so interest would be minimal.
Interest was charged on the full $17,000ish, this is how this card works. If you pay even $1 short, you might as well have paid nothing, interest will be charged on the full amount.
I usually pay my cards in full, but sometimes you just can't. So this card is... risky. More importantly, it's unethical.
BOOO Westjet Mastercard.