Darth Vader vs Starkiller (Lightsabers)

Darth Vader vs Prime Starkiller (which ever version you think is the strongest)

*lightsabers only

Vader.

Vader quite comfortably.

Vader is an unparalleled lightsaber combatant and an even more capable Force wielder.
-- Star Wars: The Force Unleashed II: Prima Official Game Guide

mmm

Ah, lightsabers only?

Not sure.

To clarify, while I believe Galen would still have superior force reserves and thus better speed, agility and endurance I believe Vader would be his superior in regards to technical skill by their respective primes.

If Galen could outlast Vader he might win but there's a chance Vader pierces his guard beforehand. So overall, I'm not really sure.

Vader honestly.

Vader, yeah.