I have purchased many of these storage containers, in various sizes. As with most OXO products, I have been extremely satisfied with them, and I would buy them again. More importantly, my wife appears to be equally impressed with her gift.
That being said, I don't think they would work as well for everyone, as they do for us. They are expensive, and they are not necessarily the best choice for a home with small children. As such, I will provide you with my observations, and leave it up to you to decide how they would fit into your personal lifestyle.
They seal flawlessly, and with great ease. I believe they are the best product available for keeping the freshness in, and the bugs out. They stack nicely, and their clear siding permits easy identification of the contents within. Their rounded corners make pouring a breeze.
These containers come in a variety of sizes, and meet all of our kitchen dry-storage needs. They work for everything from baking goods, to cereals and crackers, to bread. Yes, the two largest container sizes can hold a normal-sized loaf of bread, and keep it fresh for much longer.
They have really helped organize the pantry, which looks great, and makes it much easier to evaluate how much of a product requires replentishment, prior to shopping.
First, many of them (especially the larger sizes) are not packaged well for shipping, and they have arrived in broken condition. Fortunately, Amazon Customer Service has promptly replaced them, without delay. To me, the long-term convenience far outweighs the short-term frustration.
Second, we have not broken any of them after delivery, but we are also quite careful in their handling. I'm not sure how well they would do with small children, so be advised before you invest. I suspect a single drop on the hard kitchen floor would result in a damaged container, but I am not willing to test my hypothesis at this price.
Third, they are not dishwasher safe, except for the silicon sealing ring. For us, this has not been a major issue, but it may be a problem for others. Personally, we have found their non-pourous construction to be easy to clean, so we don't mind hand washing them.
Be aware that for stacking purposes, the containers come in three shapes (from the top view): small-square shape, large-square shape, and rectangular shape. While you can sometimes mix them for stacking, in general, I find that it is best to stick to one shape (for a particular stack).
Also, be aware that you get more bang-for-the-buck with the larger sizes. The relationship between the price of the container and the volume of storage is indirect. In short, less storage costs you more money.
In general, I find the large-square shape and the rectangular shape to be the most beneficial. They permit easy access, and they allow the buyer more options regarding what to put in them. That being said, understand that the prepackaged sets tend to come with a lot of the small-square shaped containers.
The smallest sizes have limited functionality, but can be useful for storing raisons, small candies, etc. As for the spices mentioned by the manufacturer, spices usually come in a bottle. For those that don't, I believe there are better (and cheaper) products available.
For those willing to deal with the shipping issues, the risk of future breakage, and the hand-washing, I think this is by far the best product on the market. With care, they will save you money in the long-run because: they keep things fresh, they keep the bugs out, and they make it easy to avoid the over-buying or the under-buying of groceries. They are a quality product, and they make the kitchen look great.
Whether you want to buy many of them or just a few, I generally recommend the larger sizes. They provide the best bang-for-the-buck, and permit greater flexibility. Specifically, I would start with a few of the large-square types to see if you like them as much as I do.
Thank you for those who posted before me. Much of what I have said consolidates what you mentioned before, and really helped with my purchasing decisions. For those of you still stuck in the decision-making process; good luck! I hope this helps out a little.