Enyalus
MALE DOMINANCE!!!
And you will prove how exactly marek has shown anything greater than that of DARTH SIDIOUS that could destroy entire armada's with his force storm
This has to be the most overblown feat in the SW Mythos. He ended up destroying most of the fleet, not all of it. Plus, they were flying over and/or docked inside of their planet's base of operations, taken completely by surprise and without shields or evasive combat actions. The Force Storm itself is impressive for what it can do, but I see a lot of people exaggerating about what it actually did do.
As far as the fight goes, in Scenario 1:
1. Sabers - Vader, 9/10.
2. Force - Vader, 10/10.
3. All-Out - Vader, 9/10.
In Scenario 2:
1. Sabers - Vader, 6/10.
2. Force - Vader, 9/10.
3. All-Out - Vader, 7/10.
(Sorry if the first part of my message sounded...harsh? It wasn't intended as any kind of personal insult.)
EDIT: Hell, while we're at it, let's just address the question that was intended for Elite. I'd say overall Vader is anywhere from 4th to seventh, beneath Sidious, Nihilus, Caedus, probably Bane, probably Kun (with the amulets), and even potentially Revan. The suit hurts him a lot, head-to-head. Marek I'd put considerably further down. His dueling skills only really peaked when he was fighting Vader, which might be because of his familiarity with Vader's style (sparring, being his apprentice and all...). What he does with the Force to stormtroopers and non-Force sensitives is impressive, but what has he shown against other powerful individuals? He picks up two pillars and smashes an unsuspecting Vader. That's not so great of a task. He controls a Star Destroyer that was already falling - that was pretty neat, but hardly combat worthy. He Force Chokes Kota, who wasn't even a member of the PT Jedi Council and thus, probably not nearly as powerful as some of the other PT era Jedi. His lightning didn't do anything to Palpatine (nothing really wrong with that, though)...he does pick him up and slam him down, but we don't even know if Sidious allowed that or if Marek simply tore through Sids' force defenses.
*Shrugs*