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

Execution · Pure Mechanics
Terry Cavanagh's minimalist reflex gauntlet of rotating walls measured in seconds survived.
Metal Slug 5 leans Execution (Pure Mechanics); Super Hexagon leans Execution (Pure Mechanics).
Super Hexagon leans a little harder on execution, though the gap is small.
Metal Slug 5
precise dodge/shoot run-and-gun demands
Super Hexagon
Sub-second reactions at extreme speed, pure reflex ceiling
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
Super Hexagon
No opponent, only walls
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
Super Hexagon
Pattern order randomized from a known set
Metal Slug 5 leans a little harder on optimization, though the gap is small.
Metal Slug 5
weapon pickup and route memorization
Super Hexagon
Pattern vocabulary is small, reaction is everything
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.