What is the response to those who say it is obligatory for the worshiper to make the taslim with the imam, using the hadith as evidence: "We prayed with the Prophet, peace and blessings be upon him, and we made the taslim when he made it"?

The majority of scholars hold that it is preferable for the congregant (ma'mum) to say the taslim (salutation) after the Imam has finished his taslim. If the congregant says the taslim simultaneously with the Imam, there are two opinions regarding the invalidity of the prayer: it is considered invalid according to some Shafi'i and Hanbali scholars. Among the Malikis, it is invalid if the congregant begins the taslim with the Imam. If the congregant says the taslim before the Imam, their prayer is invalid according to the Shafi'i and Hanbali schools. It is also invalid among the Malikis unless the congregant intended to separate from the Imam. Abu Hanifa, in one narration, holds that the congregant's taslim coinciding with the Imam's taslim is a sunnah, though his two companions disagreed with him.