They make good soldiers among those on furlough (9)

I believe the answer is:

restorers

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'they make good soldiers among those' is the definition.
The definition suggests an adverb but the answer is not.

'on furlough' is the wordplay.
'on' becomes 're' ('on' can be mean 'with reference to').
'furlough' becomes 'storers' (I am not sure about this - if you are sure you should believe this answer much more).
're'+'storers'='RESTORERS'

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I've seen this clue in The Independent.

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