What is the ruling on seeking refuge (Al-Isti'adha) before reciting the Qur'an in prayer, and is it obligatory or recommended?

It has been established that the Prophet, peace and blessings be upon him, used to seek refuge [with Allah] before reciting Al-Fatihah in prayer. Scholars have differed regarding the ruling on seeking refuge; some have held it to be obligatory, citing the words of Allah Almighty: "So when you recite the Qur'an, seek refuge with Allah from Shaytan, the expelled" (An-Nahl: 98). Others have held it to be merely recommended, citing the hadith of the man who prayed poorly, in which the Prophet, peace and blessings be upon him, did not mention seeking refuge, and citing the consensus of the Salaf on its sunnah status. The chosen opinion is that it is a recommended Sunnah and not obligatory.