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

Execution · Pure Mechanics
Committed rally driving where memorised stages meet precise throttle-and-slide control.

Execution · Pure Mechanics
The N64 entry whose boost-or-survive health gamble layers routing decisions onto raw speed control.
Colin McRae Rally 04 leans Execution (Pure Mechanics); F-Zero X 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.
Colin McRae Rally 04
Millisecond car control on loose surfaces is the whole test
F-Zero X
Sixty-frame control of thirty machines at top speed
F-Zero X leans a little harder on reads, though the gap is small.
Colin McRae Rally 04
Solo against the stage clock
F-Zero X
Rival AI is non-adaptive
Colin McRae Rally 04 leans a little harder on variance, though the gap is small.
Colin McRae Rally 04
Damage and surface conditions add minor unknowns
F-Zero X
X Cup random tracks are a minor mode
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Colin McRae Rally 04
Setup tuning and stage memorisation compound lap time
F-Zero X
Boost-health tradeoffs and shortcuts reward 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.