When I posted about the Sam's Club deal (which is no longer available) I mentioned that I would post a review of whether I thought it was a good savings or not.
I've been to Sam's Club a few times with my membership and find that a lot of things aren't a good deal, though they are no worse of a deal than at normal stores. I've also found some items that do save me a lot of money.
Bottled water is an excellent deal there. We don't drink it often but like to keep some on hand for car trips, picnics, etc. Much less expensive than picking up a drink on the go!
Fruit and vegetables. For example, this past week I was able to get 12oz. packages of raspberries for $2.98. I typically watch for what is on sale and that is our fruit/vegetables for that week. My kids were thrilled with the raspberries (one of their favorite fruits!).
Grains and pasta.
Birthday cake (this is where we purchased Jacob's cake, on a whim, and the customer service in the bakery department was great - they decorated it with Star Wars right then and there for us)
I wouldn't shop there weekly but do think it is worth it monthly to stock up on certain supplies. I don't know if I will renew next spring, unless they have a special like they did this year.