Well I bought the REI Novara grocery bag panniers a year ago, and unfortunately they did not hold up to well. The Nylon on the corners is worn down pretty far, the plastic on one of the bottom pieces has gone missing as well as an attachment hook, and the aluminum struts are bent. One of them is usable but I was considering buying some new ones. Any recommendations? I haven't gone out and used my REI member coupon yet so I was thinking of picking up something from them. Here are my thoughts

Ortlieb bike shopper http://www.rei.com/product/737830
I hear that their products last forever and the water proofness would be nice this summer. But I'm so used to an open top design and the ease of just throwing stuff in with sides not getting in the way.

Cannondale harvester panniers http://www.rei.com/product/765595
I like how these fold down flat and have a cover

Detours Toocan Pannier - Single http://www.rei.com/product/749998
These look nice but look like they are simply meant to stay open

I use my pannier every day to throw my back pack/ purse in. I like that my Novara panniers can fold flat instead of jutting out when I don't have anything inside of them. I think it is convenient to have an open top that I can just throw random things inside. Does anyone have any experience or thoughts with these panniers or in general?