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
Cute two-button rhythm game where everything reduces to hitting notes on beat.

Execution · Pure Mechanics
A PC rhythm game where matching colors on a spinning wheel turns charts into analog choreography.
Muse Dash leans Execution (Pure Mechanics); Spin Rhythm XD 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.
Muse Dash
Two-lane rhythm hits at high BPM are pure hands
Spin Rhythm XD
Wheel-spinning, flicks, and taps demand analog precision
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Muse Dash
Charts never adapt
Spin Rhythm XD
Charts never adapt
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Muse Dash
Fully deterministic note charts
Spin Rhythm XD
Deterministic charts
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Muse Dash
Character buffs and chart memorization help margins
Spin Rhythm XD
Chart study and controller technique choices
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.