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 · Pure Optimization
A first-person dungeon RPG testing party building and dungeon-mapping strategy.

Optimization · Pure Optimization
A faction-driven RPG-shooter where build and route planning shape every ending.
Eye of the Beholder III: Assault on Myth Drannor leans Optimization (Pure Optimization); Fallout: New Vegas leans Optimization (Pure Optimization).
Fallout: New Vegas leans a little harder on execution, though the gap is small.
Eye of the Beholder III: Assault on Myth Drannor
Real-time clicks matter but party-based, not twitch
Fallout: New Vegas
Shooter inputs with VATS assist
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Eye of the Beholder III: Assault on Myth Drannor
Monsters follow scripted behavior
Fallout: New Vegas
Scripted factions and enemies
Eye of the Beholder III: Assault on Myth Drannor leans a little harder on variance, though the gap is small.
Eye of the Beholder III: Assault on Myth Drannor
AD&D dice rolls add randomness
Fallout: New Vegas
Some loot and crit RNG
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Eye of the Beholder III: Assault on Myth Drannor
Party building, spell management and dungeon mapping lead
Fallout: New Vegas
Faction routing, perks, builds heavily rewarded
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.