up to you. do you want a tank full of damsels? its unlikely that all will survive as the get older/bigger. personally, I would never put a single damsel in my tank, but thats just me.
what other inhabitants are you considering? have you researched your new additions and their care requirements? if the tank is just finished cycling, I'd progress very slowly, nothing good happens fast in this hobby.
I understand "thats what you were told", but its YOUR tank and you need to do your own research on your tank and potential inhabitants, its part of being a responsible aquarist. Additionally, I would avoid the store that gave you such terrible advice like the plague. they have already started you off on the wrong foot, so to speak.