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
The 70s-cinema getaway driving game with famously demanding physics.

Execution · Pure Mechanics
An auto-scrolling lane shooter testing quick repositioning against memorised waves.
Driver leans Execution (Pure Mechanics); Son Son 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.
Driver
Handbrake control and pursuit driving by feel
Son Son
Lane-switching and shooting under auto-scroll pressure is everything
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Driver
Police AI is mappable
Son Son
Enemy waves arrive on fixed schedules
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Driver
Traffic adds mild unpredictability
Son Son
Occasional random bamboo bonuses, otherwise fully fixed
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Driver
City routes and mission tactics learnable
Son Son
Learning wave layouts and fruit triggers maximises survival
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.