I have one, and only really use him to negotiate contracts for the youth players that I want to keep that aren't necessarily my best prospects. For those, I'd rather do it myself.
I find its it's just a quicker way to sort the contracts for the U18s when you've got quite a few that you want to keep and don't want to spend ages sorting each deal.
Occasionally, I'll ask them to recommend me a player too, just in case they throw up anyone I wasn't aware of.