Possess top-class modern technology to gain advantage (4,3,4,2,2)

I believe the answer is:

have the best of it

'gain advantage' is the definition.

'possess top-class modern technology' is the wordplay.
'possess' becomes 'have' ('have' can be a synonym of 'possess').
'top class' becomes 'thebestof'.
'modern technology' becomes 'it' (Information Technology).
'have'+'thebestof'+'it'='HAVE THE BEST OF IT'

'to' acts as a link.

I've seen this clue in The Times.

Want a hint initially instead of a full solution? Install my app