This bag is extremely sturdy and stiff enough to stand open but still 'crushable' for storage. Seems like it will last forever. I got it b/c I go out on a boat frequently for work and need a place for towels, camera, raincoat and other misc stuff. The measurements are accurate however when I measured them out prior to ordering I still did not picture the bag being as large as it is! If it is for an outing for 3 or more I would bet this is the size you need, For one person it is way too big though and I am going to order their dolphin bag instead. The pockets on the outside will hold a lot but I would actually prefer a few smaller pockets too. All in all a great bag!
UPDATE: I ended up going back to order a smaller size 'dolphin' bag and mentioned that it would be nice if they offered a bag with a solid (rather than mesh) bottom for non beach uses and for a very small fee she made one that way for me. I even got to pick the colors. It took maybe 1 extra day over ordering what is listed on the website. The seller communicates fast and is very friendly and helpful! I strongly recommend them, and would not hesitate to ask for what I wanted from them.