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
Tests off-road handling and freeform route choice across an enormous open map.

Execution · Practiced Mastery
Aggressive circuit racing testing car control over memorisable tracks and braking points.
Fuel leans Execution (Pure Mechanics); Race Driver: Grid 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.
Fuel
Off-road vehicle control through weather events is the core test
Race Driver: Grid
Aggressive wheel-to-wheel car control is the core demand
Race Driver: Grid leans a little harder on reads, though the gap is small.
Fuel
AI racers rubber-band on scripts; online is thin
Race Driver: Grid
Online racing adds light opponent positioning awareness
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Fuel
The huge map is scripted-but-unknown until explored
Race Driver: Grid
Damage outcomes add slight unpredictability to contact
Race Driver: Grid leans a little harder on optimization, though the gap is small.
Fuel
Route choice across open terrain rewards planning
Race Driver: Grid
Braking points, lines and flashback management are learnable
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.