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

Execution · Pure Mechanics
Retro Studios' notoriously tough revival of Donkey Kong Country with relentless set-piece levels.

Execution · Pure Mechanics
The last mainline Guitar Hero, wrapping its setlist in a quest with score power-ups.
Donkey Kong Country Returns leans Execution (Pure Mechanics); Guitar Hero: Warriors of Rock leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country Returns
Demanding rocket-barrel and mine-cart sections, strict timing
Guitar Hero: Warriors of Rock
Expert charts and the brutal 2112 finale
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country Returns
Scripted hazards, no adaptation
Guitar Hero: Warriors of Rock
Nothing adapts
Donkey Kong Country Returns leans a little harder on variance, though the gap is small.
Donkey Kong Country Returns
Hidden puzzle pieces, fixed once found
Guitar Hero: Warriors of Rock
Deterministic charts
Donkey Kong Country Returns leans a little harder on optimization, though the gap is small.
Donkey Kong Country Returns
KONG letters and time attack routes are learnable
Guitar Hero: Warriors of Rock
Power-up choices and star power routing
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.