head to head
Arma 3 asks more than Call of Duty: Modern Warfare 3, and the gap is variance.

Execution · Grand Arena
Open military simulator and PvP sandbox.

Execution · Pure Mechanics
A fast-paced military shooter where twitch aim against other players is the core test.
Arma 3 leans Execution (Grand Arena); Call of Duty: Modern Warfare 3 leans Execution (Pure Mechanics).
Call of Duty: Modern Warfare 3 leans a little harder on execution, though the gap is small.
Arma 3
Bullet drop, stance, sway, weight all matter
Call of Duty: Modern Warfare 3
aim and reflexes decide most engagements
Arma 3 leans a little harder on reads, though the gap is small.
Arma 3
PvP and milsim ops reward prediction
Call of Duty: Modern Warfare 3
predicting human opponent positioning and habits
Arma 3 leans clearly harder on variance.
Arma 3
Mission scripts and AI behavior vary
Call of Duty: Modern Warfare 3
spawn placement and loadout drops vary
Arma 3 leans clearly harder on optimization.
Arma 3
Loadout planning and tactics solvable
Call of Duty: Modern Warfare 3
loadout tuning and map knowledge help
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.