head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Execution · Practiced Mastery
Falling-pill placement speed against virus layouts, with light versus pressure.

Execution · Practiced Mastery
A cover-shooter Rainbow Six blending tactical room-clearing with solid gunplay.
Dr. Luigi leans Execution (Practiced Mastery); Tom Clancy's Rainbow Six: Vegas 2 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.
Dr. Luigi
Fast pill placement under pressure decides clears
Tom Clancy's Rainbow Six: Vegas 2
Cover-based gunfights still punish poor aim
Tom Clancy's Rainbow Six: Vegas 2 leans a little harder on reads, though the gap is small.
Dr. Luigi
Versus mode adds mild tempo prediction against humans
Tom Clancy's Rainbow Six: Vegas 2
Multiplayer brings some human adaptation; AI is scripted
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Dr. Luigi
Pill colours and virus layouts vary each round
Tom Clancy's Rainbow Six: Vegas 2
Enemy placements partially unknown per encounter
Tom Clancy's Rainbow Six: Vegas 2 leans a little harder on optimization, though the gap is small.
Dr. Luigi
L-pill placement patterns and combo setups are learnable
Tom Clancy's Rainbow Six: Vegas 2
Room-clearing order and squad commands are solvable tactics
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.