The big question is though, which one should you choose?
Killstreaks are made up of the number of consecutive kills you achieve.
Scorestreaks push the player to complete game mode objectives rather than just purely doing it for the kills.
If there’s no objective here, then earning points towards your score won’t make a difference.
For this then, you may opt for Killstreaks.
In the case of pretty much every game mode in Modern Warfare 3 then, you should choose Scorestreaks.
To do so, head to the lobby and tab to the ‘Weapons’ page.
That’s everything we have to hopefully inform your decision between Killstreaks and Scorestreaks in Modern Warfare 3.
