I was just wondering what is more commonly used in Japan, in terms of formality? I feel like I remembered reading somewhere that Genki: 3rd (or 2nd?) Edition made note that じゃないです is more commonly used colloquially than じゃありません (ie. talking with a server at a restaurant “formal” vs. business “formal”), is this true? Or are both equally as acceptable?
I’m not looking to make any business relationships lol so I just want to make sure I’m approaching a situation the right way.