I love these bags!  I saw the positive reviews but honestly was slightly put off by the price, so I was pleased when I got them as a Christmas gift last year.  Turns out they are totally worth the money.  First off, you do get five bags, so honestly when you do the math it's not that bad.

Pros:
1. They are fully machine washable and the material they are made from has just enough slipperiness to it that simple spills/leaks can often just be rinsed off.  (Something to think about when choosing bags to reuse, you don't want cross contamination between shopping trips.)
2. They hold way more than you would think.  Because they fold up so small you'd think they had a relatively low carrying capacity, but I've been shocked at what I've been able to fit in them.  Taking all five to the grocery store is often all I need for my trip and one or two is more than enough for trips to most other stores.
3. Because they come in a set I'm less likely to be without one.  I personally don't use their little collection pouch all that much, but instead tend to stash them in various places...one in the car, one in my bag, one at work etc.  My biggest issue with reusable bags is that I tend to forget them on my way out the door and having five bags that can be so compact really helps with that.
4. The patterns are really cute and I love the variety.  I've gotten compliments on them before and have had several people ask where I got them.
5. They are versatile. I literally use them for everything; one holds my towel and sunblock when going to the pool, I carry supplies for school (I'm a teacher) in them and recently even took one on a trip to use as a beach bag.

Cons:
There aren't really a lot of these.  The only ones I could think of are:
1. While I love the fabric it's not unbleached, eco-friendly hemp or cotton...not sure about the environmental impact of it's creation.  Could be totally ecofriendly, I have no idea honestly, but these aren't your typical cream colored shopping bags.  You can decide if that matters to you or not, it really doesn't to me since I plan on having them forever.
2. They include a snap for rolling them up and into their small little bundles.  When the bag is open that means you have this little fabric strap and snap hanging off the bottom.  This really doesn't bother me at all, but it may be a "look" that could put some people off from a visual perspective.
3. They aren't cheap.  Again, I'll restate that when you consider there are 5 of them it's not that bad really.  But they aren't the cheapest bags on the market.

Considering how much I love them, I'm planning on copying my aunt and giving some out this year as gifts myself!