In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
The virtue in reference is quoted by Sheikul Hadith Hadrat Maulana Muhammad Zakariyya Kaandhalwi Rahmatullahi Alaih in Fazaa’il-E-Aamil (Virtues of Quran Page 322; Zam Zam Publishers; Ed.September 2011). Hadrat Moulana Muhammad Zakariyya Saheb was an authority in ahadith.
Hereunder are virtues of each of the Surahs that you referred to:-
Surah Ar-Rahman describes the boons and bounties of Almighty Allah in this world and in the Hereafter. Whosoever recites Surah Ar-Rahman Allah Subhana wa Ta’Ala will have mercy upon him.[1]
Whoever recites Surah Wakiah in the nights will be protected from poverty. (Mariful Quran Vol 8 Pg280).
It is reported in Abu Dawud, Tirmidi and Nasai that Sayyidna Irbad Ibn Sariyah Radiallahu Anhu has reported that Rasulullah Salallahu Alaihi wa Salam used to recite Al-Musabbhat ( 5 Surahs including Surah Hadid) before going to sleep. He Salallahu Alaihi wa Salam said in them is a verse that is more meritorious than a thousand verses.
According to Ibn Kathir the best verse in Surah Hadid is verse 3 - :{هُوَ الْأَوَّلُ وَالْآخِرُ وَالظَّاهِرُ وَالْبَاطِنُ وَهُوَ بِكُلِّ شَيْءٍ عَلِيمٌ}. He is the First and the Last, and the Manifest and the Hidden, and He is All-Knowing about everything.[2]
And Allah Ta’āla Knows Best
Mufti Saeed Ahmed Golaub
Islamic Solutions
Jamaica
References
[1]:قَالَ: وَمَنْ قَرَأَ سُورَةَ الرَّحْمَنِ، رَحِمَ اللَّهُ ضَعْفَهُ، وَأَدَّى شُكْرَ مَا أَنْعَمَ اللَّهُ عَلَيْهِ. ترتيب الأمالي الخميسية للشجري (1 / 132)
[2]: ثُمَّ قَالَ: «هَلْ تَدْرُونَ مَا الَّذِي تَحْتَ ذَلِكَ» ؟ قَالُوا: اللَّهُ وَرَسُولُهُ أَعْلَمُ. قَالَ: «فَإِنَّ تَحْتَهَا أَرْضًا أُخْرَى، بَيْنَهُمَا مَسِيرَةُ خَمْسِ مِائَةِ سَنَةٍ» حَتَّى عَدَّ سَبْعَ أَرَضِينَ، بَيْنَ كُلِّ أَرْضَيْنِ مَسِيرَةُ خَمْسِ مِائَةِ سَنَةٍ. ثُمَّ قَالَ: «وَالَّذِي نَفْسُ مُحَمَّدٍ بِيَدِهِ لَوْ أَنَّكُمْ دَلَّيْتُمْ بِحَبْلٍ إِلَى الأَرْضِ السُّفْلَى لَهَبَطَ عَلَى اللَّهِ» . ثُمَّ قَرَأَ {هُوَ الأَوَّلُ وَالآخِرُ وَالظَّاهِرُ وَالبَاطِنُ وَهُوَ بِكُلِّ شَيْءٍ عَلِيمٌ} [الحديد: 3]
سنن الترمذي ت شاكر (5 / 404)