"To jest bardzo bezpieczne auto" it is also a good answer.
I agree, you should report.
Are you Polish, from South-East (Małopolska, Galicja itp?). Supposedly "auto" is very informal in the rest of country?
I'm from the central Poland (south of Warsaw) and it's not considered informal, maybe slightly more informal than 'samochód' but still you can use it in most situations.
I agree, for some reason, dictionaries, and some people here disagree.