When are Surat Al-Waqi'ah and Al-Mulk recited, and is there any virtue in reciting them after Maghrib?

Authentic hadiths have been reported concerning the virtues of Surat Al-Mulk, among them that the Prophet, peace and blessings be upon him, would not sleep until he recited Surahs Al-Sajdah and Al-Mulk. It is recommended to recite it every night before sleeping. As for Surat Al-Waqi'ah, no specific time has been mentioned for its recommended recitation, and the hadith (definition) reported concerning the virtue of reciting it every night is weak. A Muslim may recite whatever he wishes from the Qur'an at any time, and there is no harm in reciting the two surahs after Maghrib, but dedicating this time is not a Sunnah (definition).