head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Pure Optimization
A faster-paced action RPG where class builds and rival paths shape the run.

Optimization · Pure Optimization
A VATS-heavy wasteland RPG won by perk and build optimization.
Dragon Age II leans Optimization (Pure Optimization); Fallout 3 leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Age II
Faster action combat, modest input demand
Fallout 3
VATS-leaning combat, low aim demand
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Age II
Wave-based scripted enemies
Fallout 3
Scripted enemies
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Age II
Low randomness in encounters
Fallout 3
Loot rolls, SPECIAL checks
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Dragon Age II
Class builds and friend/rival paths reward planning
Fallout 3
Perk and build planning carries the run
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.