My DH works thereso I love it! He works out of a separate company within Costco though, so we still have to pay for our membership. We used to get the executive membership, but found that the cheques we were getting were smaller than the price of the executive membership, so we went back to the regular one.
They have the cheapest price on certain stuff like yogurt drinks ($8.99 for 16) and veggie straws ($4.99 for a ginormous bag) and their produce is a really good price too I find.