Ceramic is not the enemy. It's the nicest thing in most kitchens.
This comparison gets written as though one material has to lose. It doesn't. Ceramic and steel are good at almost exactly opposite things, and if you know which is which the choice makes itself.
What ceramic wins, and we're not going to argue
The oven. Ceramic goes in it. Steel doesn't go in a microwave at all, and while it's fine in an oven, it isn't a baking dish.
The microwave. Ceramic reheats. Steel cannot, ever. If your storage container needs to be your reheating vessel, this comparison is already over and ceramic won.
The table. A glazed ceramic dish is a nice object. Steel is a tool that happens to look clean. We're not going to claim a mirror finish competes with a hand-thrown bowl on an open shelf, because it doesn't.
Seeing in. Neither is transparent, so this one's a draw and both lose to glass.
What steel wins
The drop. This is the big one. Ceramic chips and cracks, and once it's chipped it's done — a cracked glaze isn't a cosmetic problem, it's a place for water to get into the body of the piece. Steel dents and carries on. A dent is an aesthetic event, not a functional one.
The bag. Ceramic storage containers are heavy and they are not built to be carried to work with soup in them. Steel is the material for anything that moves.
The decade. We guarantee the steel for ten years, rust included. We can do that because the failure mode of steel is basically cosmetic. Nobody guarantees ceramic for ten years, and it isn't because they're stingy.
The glaze question
Here's the thing that never makes it into these comparisons.
Ceramic itself is inert. The glaze on top of it is a different material, and it is regulated — EU Directive 84/500/EEC sets legal limits on how much lead and cadmium a ceramic food-contact article may release, tested in acetic acid. Limits exist for a reason: some glazes release some. Current limits run roughly 1.5–4 mg/L for lead and 0.1–0.3 mg/L for cadmium depending on the article, and the EU is currently reviewing them downward, with new limits proposed for aluminium, arsenic, barium, cobalt, chromium and nickel.
Compliant ceramic from a real manufacturer is fine. It's tested, there's a declaration of compliance behind it, and we're not suggesting otherwise. But it makes the honest point: a glaze is a materials list you can't read. You can't tell by looking, and the unmarked bowl from a holiday market has no declaration behind it at all.
With steel there are two materials and we name both: 304 stainless steel and one food-grade silicone seal. We don't claim steel is inert — it isn't, and we've said so. We claim you can know what it is.
The environment: we're not going to claim this one
You'd expect us to say steel wins here. We won't.
Ceramic firing is energy-intensive. Steel is mined and smelted, and the Dutch Consumentenbond found steel bottles came off worst of the materials they compared. Both numbers are real. Whichever one you own longest is the one that wins, and neither material makes that decision — you do.
So which
If it lives on a shelf, goes in the oven, gets reheated and never leaves the house: ceramic. It's better at that, and it's nicer.
If it goes in a bag, gets dropped, gets opened at a desk and needs to still close properly in 2036: steel.
Most kitchens want some of each. Ours does.
If it's the second one, our containers close with a steel lid — not a plastic one — and you can read every gap we have before you buy.
Replace the plastic.
Food should be stored without doubt.