Litres do not describe the footprint
Two containers with the same capacity can occupy very different shelf space. Measure the usable depth and height in your fridge, including the space needed to lift a lid. A tall narrow container might fit a bottle shelf but be inconvenient for a portion you want to reheat evenly. A low broad one may suit that meal while taking up more room.
Think about empty storage too. Nesting containers save cupboard space, but lids can become a separate pile. Matching lid sizes across several useful containers may be more convenient than buying a set with a different lid for every shape. Check which parts are actually shared rather than assuming similar-looking pieces will seal together.
A closure has more than one job
An airtight claim and a leakproof claim are not interchangeable. For soup carried in a bag, look for an explicit statement about transport and follow any restrictions on liquids or temperature. Test the closure with water in an appropriate place before trusting it beside a laptop. A lid that is easy for one person to close may be difficult for another.
Inspect grooves and removable seals. They need to be accessible for cleaning and refitted correctly. A complicated closure can be worthwhile for transport but unnecessary for dry ingredients kept in a cupboard. Choose the mechanism around the food and destination, not around the greatest number of clips.
Check each part's permitted uses
Freezer, microwave and dishwasher permissions may differ between the base and lid. Read the instructions for venting and reheating, and do not infer that a glass container's plastic lid has the same temperature limits. A container does not make food safe indefinitely; use storage guidance for the food itself and label leftovers so you know when they were prepared.
Before committing to a large set, try one or two useful sizes. See whether they fit your shelves, portions and cleaning routine. Check for spare seals or lids if those are replaceable. The most helpful set is the one whose pieces circulate through your kitchen, rather than the one that offers the largest total litre figure.
