I know in winemaking it is always preferable to age in bulk. If you are still trying to get anything from the trub (chocolate, fruit, whatever) then aging in bulk is required.
Once all of the yeast and late addition results are as you wish, rack into an aging vessel that you can purge all the headspace from...carboys work, kegs are better.
When I age in kegs I actually begin carbonation at the same time using low pressure, it makes flavor sampling a little more accurate for me.
Something is always fermenting....
"It's Bahl Hornin'"
Kegged: Bourbon Barrel Imperial Stout
On Deck: German Lager