DarkRP MilitaryRP or sandbox

DarkRP and MilitaryRP fall into the same category, they both use the DarkRP Schema pretty sure. But its fun because you have something to fight for, something to work for, you don't get everything handed to you on the table.
Sandbox inspires deathmatch and creativity, but it gets boring quickly, so i'd say DarkRP or some other forms of SeriousRP in general.