Many people wonder about stainless steel (shiny metal) pet bowls that are used for water and food. One main concern is if the metal will tarnish or not? I can say that these stainless steel bowls are the best out there.
Even though I would prefer a continuous feeder, ceramic or cute plastic bowl, these stainless steel bowls actually hold up it seems forever and are very easy to clean. We put our bowls in the dishwasher when needed, but normally hand wash with soap and a sponge.
We recently purchased this 4 inch deeper stainless steel bowl because our cat and dog drink from the same dish - no matter that we have two bowls of water. The other bowl is smaller and about 2 inches high. But we were using a wider bottom stainless bowl that had a rubber band around the bottom edge. The only problem with those bowls is that food, dirt, dust, etc. gets trapped inside and between the black rubber and the dish. So when we saw this deeper version of the smaller one we really liked, we bought it.
This pet dish is dishwasher safe, rust proof, and hygienic.
I find that these dishes don't tend to "gum up" with slimy residue like plastic dishes tend to do. But then you won't have that issue if you clean your pet dishes every day when you change their water and give them fresh water every day.
In the 17 years that I have had my cat and used the smaller stainless dish, I have yet to see the first sign of rust. There are no tiny spots that would indicate any possibility of this either. So, instead of going for the cutesy bowls, we went for the practical and hygienic kind.