Wa `alaykum as-salamu wa rahmatullahi wa barakatuh.

 

This is called Salat Al-Tasabeeh or the prayer of lot of praises to Allah.

 

Most of the Hadiths narrated by Abu Dawud and At-Tirmidhi are in the status of weak. For that, many scholars do not approve of it.

 

Other scholars like An-Nawawi made it permissible as there more than one narration that might give legitimacy to the prayer.

 

The way I look at it, if someone said it is not allowed I respect his view but if another did pray it I do not make an issue out of it.

 

Almighty Allah knows best.