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
A run-and-gun arcade shooter that is almost pure twitch execution.

Execution · Pure Mechanics
Pure reaction timing - two buttons, escalating speed, zero forgiveness for mashing.
Metal Slug 5 leans Execution (Pure Mechanics); One Finger Death Punch 2 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.
Metal Slug 5
precise dodge/shoot run-and-gun demands
One Finger Death Punch 2
Two-button precision timing at extreme speed is everything
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Metal Slug 5
enemy waves are fully scripted patterns
One Finger Death Punch 2
Enemy approach cues are fully telegraphed scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Metal Slug 5
minor drop and spawn randomness
One Finger Death Punch 2
Wave composition shuffles slightly between rounds
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Metal Slug 5
weapon pickup and route memorization
One Finger Death Punch 2
Skill loadouts and restraint from mashing form light strategy
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.