Yeah, well worth it for restaurants and other things. We get the paper Sat & Sun, and have the premium card. There is a standard version where sometimes instead of 20% off you'll get 15% off. We'll generally go to 2 restaurants a month with it, normally get 20% off. For us it paid for itself when we furnised our apartment, got 25% off a fairly pricey sofa from one of the shops in Buenos Aires design. We'd probably have ordered the weekend paper anyway as it's nicer to have a physical paper to read at the weekend. Some of the supermarkets have a La Nacion discount day, Coto have it on tues or weds i think, we go in then and stock up on household essentials, cleaning products etc..any non-fresh food basically. 20% off everything..makes a difference when you see that 1k become 800 pesos.
Different to groupon etc in that the discount is applied to your purchase, rather than paid for in advance. i.e. a 400peso bill becomes 320 at the point of purchase rather than buying an offer in advance. It is different to some of the bank discounts where the bank refunds you the discount to you after the purchase. You bank might offer 20% on a certain day but you pay 400 and receive the 80 from the bank a few days later.
Very useful for the peso wage slaves amongst us. Like everything you have to use it to get value from it.