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

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

Execution · Pure Mechanics
A reflex-driven isometric runner about dodging hazards at high speed.
Donkey Kong Country Returns leans Execution (Pure Mechanics); SegaSonic the Hedgehog 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
SegaSonic the Hedgehog
Trackball reflexes dodging hazards at speed decide survival
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
SegaSonic the Hedgehog
No opponent, only environmental traps
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country Returns
Hidden puzzle pieces, fixed once found
SegaSonic the Hedgehog
Hazards are fixed once a course is learned
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Donkey Kong Country Returns
KONG letters and time attack routes are learnable
SegaSonic the Hedgehog
Memorizing the optimal route through each stage helps
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.