head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

Optimization · Practiced Mastery
Grim stealth horror about luring scripted hunters into executions.

Optimization · Practiced Mastery
Series finale blending stealth with active battlefields and heavy cinematics.
Manhunt leans Optimization (Practiced Mastery); Metal Gear Solid 4: Guns of the Patriots leans Optimization (Practiced Mastery).
Metal Gear Solid 4: Guns of the Patriots leans a little harder on execution, though the gap is small.
Manhunt
Stealth timing on executions
Metal Gear Solid 4: Guns of the Patriots
flexible gunplay alongside sneaking
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Manhunt
Hunters patrol on scripts
Metal Gear Solid 4: Guns of the Patriots
battlefield factions act on scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Manhunt
Patrol noise reactions add small unpredictability
Metal Gear Solid 4: Guns of the Patriots
mid-battle chaos mostly cosmetic
Metal Gear Solid 4: Guns of the Patriots leans a little harder on optimization, though the gap is small.
Manhunt
Shadow routes and lure tactics are learnable
Metal Gear Solid 4: Guns of the Patriots
camo, gear, and route knowledge per act
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.