What do we say when the Mu'adhdhin says "Prayer is better than sleep"?

The Maliki, Shafi'i, and Hanafi madhhabs hold that whoever hears the muezzin say: "Prayer is better than sleep" should respond with: "You have spoken the truth and acted righteously." Imam al-Nawawi mentioned this well-known saying in "Al-Majmu'". However, al-Rafi'i narrated another opinion, which is to say: "The Messenger of Allah, peace and blessings be upon him, has spoken the truth; prayer is better than sleep." As for al-Kasani al-Hanafi, he stated in "Bada'i' al-Sana'i'" that the listener does not repeat what the muezzin says, but rather says: "You have spoken the truth and acted righteously" or something else for which they will be rewarded. Al-Mardawi al-Hanbali said in "Al-Insaf" that the correct view in the madhhab is to say only: "You have spoken the truth and acted righteously" upon hearing the tathwīb.

Scholars have differed on the issue of responding to the tathwīb. Some have said that saying: "You have spoken the truth and acted righteously" is merely a preferred custom (istihsan) and not a Sunnah upon which one can rely. Accordingly, whoever says "You have spoken the truth and acted righteously" upon hearing the muezzin say "Prayer is better than sleep" has done well. Similarly, whoever imitates him by saying: "Prayer is better than sleep" also does well, based on the hadith: "When you hear the call [to prayer], say what the muezzin says."