I'm not impressed with this empty high street outlet (5)
I believe the answer is:
boots
'high street outlet' is the definition.
'i'm not impressed with this empty' is the wordplay.
'i'm not impressed' becomes 'boo'.
'with' says to put letters next to each other.
'empty' says to hollow out the word (remove centre letters).
'this' with its middle taken out is 'ts'.
'boo'+'ts'='BOOTS'
(Other definitions for boots that I've seen before include "shoe cleaner" , "Footwear" , "Kicks" .)