Andy M. said:
I do that too. I buy boneless beef sirloin strips, tenderloins, etc. and slice them into steaks and roasts. I do the same with pork loins. I typically use a chef's knife or even a slicer (carving knife). For slicing whole cuts of meats, you need a stiff sharp blade to give you straight cuts so each steak is uniform in thickness.
A filet knife for fish is completely different. It's a thin flexible blade you can easily work to cleanly remove the flesh from the sides of a fish.
I don't think yo need a set. One knife for slicing meats and another for fileting fish. Depending on what you already have, you may only need one knife.