Big brewers use stainless tanks almost exclusively, so there shouldn’t be any issue taste wise for fermentation. If you’re brewing something with very subtle flavors (like a mead or something similar) I’d be leery about bulk aging 5Gal in steel, but I don’t think it would impact it too much.

Cleaning wise-echoing the other comment, anything really acidic or really basic can etch it, but assuming you’re diluting to the right strength and all that, you should be fine. If there are any valves or false bottoms, etc. you will have to remove those occasionally to properly clean them.