Former quality discussed in legendary brand (9)
I believe the answer is:
excalibur
'brand' is the definition.
(I know that Excalibur is a brand)
'former quality discussed in legendary' is the wordplay.
I cannot really understand how this works, but
'former' could be 'ex' (prefix meaning former or onetime) and 'ex' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for excalibur that I've seen before include "Traditional weapon" , "King Arthur's magical sword" , "The legendary sword of King Arthur" , "King Arthur's magic sword" , "Legendary weapon" .)