I have placed in here a couple hard-cooked eggs, an avocado, some tomato, onion, cilantro and iceberg lettuce. The three small plastic containers hold a blend of grated cheeses and some jalapeno rings. I find that using the small containers for cheeses and such helps with portion control also. These small containers can be purchased in bulk at Sam's Club.
I use Ziploc containers. They do a good job of keeping food fresh and they are not expensive. And they are durable. Most of my containers have been through the dishwasher numerous times. Also, if you lose one it's OK because you didn't invest enormous amounts of money in expensive containers.