I'd say that it's roughly 20% more expensive than average (at least that's what I see when I compare to a supermarket like Leclerc) but they're well located, easy walking distance from the center of the cities and perfect for people like me who don't want to get into a car to go shopping.

They also have an online delivery service which works really well.

They do tend to have a bit more choice when it comes to fine foods and sell some premium brands like Valrhona that you wouldn't necessarily find in normal supermarkets.