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 · Pure Mechanics
Absurd physics limb control tested under a timer atop a tower of friends.

Execution · Pure Mechanics
Holding clean lines at speed through traffic on memorisable point-to-point roads.
Mount Your Friends leans Execution (Pure Mechanics); The Need for Speed leans Execution (Pure Mechanics).
Mount Your Friends leans a little harder on execution, though the gap is small.
Mount Your Friends
QWOP-like limb control under a timer is the entire challenge
The Need for Speed
Holding racing lines at speed through traffic is the test
Mount Your Friends leans a little harder on reads, though the gap is small.
Mount Your Friends
Rivals shape the tower but climbing is solo execution
The Need for Speed
AI rivals and police follow fixed behaviour
The Need for Speed leans a little harder on variance, though the gap is small.
Mount Your Friends
The stack you face is visible, nothing hidden
The Need for Speed
Traffic patterns add mild run-to-run noise
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Mount Your Friends
Grip-route planning up the pile helps marginally
The Need for Speed
Track knowledge and car choice settle quickly
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.