For us living out of Calgary, using a parking lot at the airport is the most viable option for us. A cab ride for us simply isn't an option.
I've used Park & Jet a few times without incident. I haven't had to wait long for a shuttle, they get there quickly and the price is reasonable.
They accept AMA cards at checkout too.
The only gripe would be the small parking spaces when trying to sneak a truck into a spot. Make sure you turn in your side view mirrors!