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

Execution · Practiced Mastery
Wrangling high-speed 3D movement through fixed stages and boss scripts.

Execution · Practiced Mastery
Precise stunt driving over loops and jumps plus route optimisation per track.
Sonic Adventure DX: Director's Cut leans Execution (Practiced Mastery); Stunts leans Execution (Practiced Mastery).
Stunts leans a little harder on execution, though the gap is small.
Sonic Adventure DX: Director's Cut
High-speed 3D control and jank-wrangling demand real hands
Stunts
Threading loops and jumps without crashing demands precise driving
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Sonic Adventure DX: Director's Cut
Chaos bosses run fixed phase scripts
Stunts
AI opponents follow fixed lines
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Sonic Adventure DX: Director's Cut
Stage layouts and upgrades never change
Stunts
Tracks are known; physics quirks barely random
Stunts leans a little harder on optimization, though the gap is small.
Sonic Adventure DX: Director's Cut
Speedrun routing and A-rank paths are learnable systems
Stunts
Optimal lines and car choice per track are solvable
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.