I have tried all of them and the one that I liked the best was Passport to Fun. I still use that one just about every month. I mean, you can get Wendy's $10 certificates for $8. That right there is a good deal.
One hint--My mom called them toward the end of the free trial to cancel and they offered her the whole year for $20. So including the $1 trial, it was $21 for the whole year. You can make up $21 just in Toys R Us gift cards to use at Christmas.
As for the other ones, I didn't like them at all. You could not get a lot of real gift certificates, only online "discounts" that you can get through any coupon and rewards site. I can't remember specifically which ones were like that, but Savings Smart comes to mind.
