Basically you really want to sign the token one (there is different token costs/more expensive better) if you need a player in that role. I missed my first youth and regret it.
The one that cost no token you can sign & sell, or just let go. You will find that one is very slow trainer. This I know because I have signed them and they are painful trainers, but hey if you need a guy in that spot you can give 'em a try out.