I'm a fan of Korin or Mac knives. I use a deba (cleaver) for butchering whole fish and animals because it can cut through bone or finely slice a filet. Then I use a small paring knife for fine items like garlic or quail. And I use a 10-inch chef's knife for most everything else. Those are the only three knives I use! I like them a lot for their durability and consistency in sharpness. Of course I also will bring out my oyster knife and bread knife.
I keep them in their original boxes and then put them into another box, which I lock. They always go back in their place at the end of the day. I clean them after every use. They are stainless steel blades, so they just need warm soapy water.
I use a 1,000 grit stone to reshape the edges every other week, then a 6,000 grit stone to polish and fine tune the blade every other day. You can think of it like this: Stones come in different grits, just like sandpaper. The lower the number, the harder the stone will be on your blade. For knives made with finer edges, like mine, I use the smoothest sharpeners, so it doesn't grind off much of the metal as I sharpen.
If I am cooking for business, yes. Otherwise I have a couple at home that are great.
I enjoy filleting whole fish, and doing fine brunoise (extremely small dicing) with things like garlic, shallots and onions. My favorite technique is using a sharp chef's knife to prepare fish for ceviches, tartares and sashimis … you get those really thin slices. It's fun to work with raw fish.
A sharp one.