head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Practiced Mastery
A handheld Ratchet & Clank adventure shrunk down for PSP with armour collecting.

Execution · Practiced Mastery
An open-structured Game Boy Mario where six zones guard coins that unlock Wario's castle.
Ratchet & Clank: Size Matters leans Execution (Practiced Mastery); Super Mario Land 2: 6 Golden Coins leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Ratchet & Clank: Size Matters
Run-and-gun platforming on PSP controls
Super Mario Land 2: 6 Golden Coins
Forgiving jumps but bosses still test timing
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Ratchet & Clank: Size Matters
Enemies are scripted
Super Mario Land 2: 6 Golden Coins
No adaptive opposition anywhere
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Ratchet & Clank: Size Matters
Fixed levels and drops
Super Mario Land 2: 6 Golden Coins
Secret exits hidden until discovered
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Ratchet & Clank: Size Matters
Weapon upgrades and armour-set collecting
Super Mario Land 2: 6 Golden Coins
Nonlinear zone order and secret levels reward planning
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.