Were getting somewhere now. What im asking is if it was a side-by-side comparison which would lag less: Me hosting a server with 12 people, or me joined to my dedicated server with 12 people.
You have more control in a dedicated server.
There are cool commands like talk("phrase goes here"); that allows you to speak as the console.
It's fun to mess with.

announce("phrase goes here"); is something similiar, except you talk with yellow text with no nickname.
You do those commands with the dedicated server console.
Only problem is that to kick/ban someone, you HAVE to be IN the server. For some reason you can't kick/ban from dedi's console.
On a Listen server (hosting a game by pressing Start Game > Internet > Start), you would need to be on Blockland all the time to keep hosting it.