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 · Practiced Mastery
A kart racer with an adventure structure and three vehicle types, lighter on item chaos than its rivals.

Execution · Practiced Mastery
An isometric combat racer set to metal covers, mixing vehicle upgrades with weaponized laps.
Diddy Kong Racing leans Execution (Practiced Mastery); Rock n' Roll Racing leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Diddy Kong Racing
Drift boosts across car, hovercraft and plane demand precision.
Rock n' Roll Racing
Isometric cornering and weapon timing carry races.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Diddy Kong Racing
Multiplayer item duels add mild prediction; AI is scripted.
Rock n' Roll Racing
Two-player duels add slight prediction; AI is scripted.
Diddy Kong Racing leans a little harder on variance, though the gap is small.
Diddy Kong Racing
Balloon pickups and items inject moderate randomness.
Rock n' Roll Racing
Weapon exchanges and pickups create chaos.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Diddy Kong Racing
Vehicle choice, balloon upgrade routes and boss strategies converge.
Rock n' Roll Racing
Upgrade purchases and planet-by-planet earnings are plannable.
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.