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

Execution · Practiced Mastery
Claustrophobic post-apocalyptic shooter where bullets double as currency.

Optimization · Practiced Mastery
The sequel takes Torque to Baltimore to fight slavery-themed monsters while his morality shapes the story.
Metro 2033 leans Execution (Practiced Mastery); The Suffering: Ties That Bind leans Optimization (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Metro 2033
scarce-ammo gunfights punish sloppy aim
The Suffering: Ties That Bind
Gunplay and monster-form brawling demand decent reflexes
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Metro 2033
mutants and bandits follow scripts
The Suffering: Ties That Bind
Enemy archetypes run scripted behaviour, never adapt
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Metro 2033
hidden moral points and supplies first run
The Suffering: Ties That Bind
Unknown encounters and branching morality first time
The Suffering: Ties That Bind leans a little harder on optimization, though the gap is small.
Metro 2033
ammo-as-currency economy and stealth routing
The Suffering: Ties That Bind
Combat systems and morality routes converge with knowledge
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.