Quoted from wesman:
For total Vader Badassery, I'd say his conflicts as Anakin, dealing with the weight of his mother being tortured, then slaying those skanky skunky Tuskens and fams, was more drama inducing.
I rewatched the Rogue One end scene after you posted this, and unofficially I'd say scene 38, the redo, is far more aggressive and nasty than Rogue One.
But the prior scene I mentioned, and him telling Padme there was a rampage, lying to her, to get her on his side after he murdered children and anyone that stood in his way, was far more psychotic and ruthless as "Vader" than a chip chop scene leading from Rogue One to a New Hope.
His scene with Padme later, telling her of his betrayal to his entire life, has more weight for me also.
The moments where Anakin has to face his decision making, is far more weighty and consequence filled than a quick hack and slash of some goofy helmet wearing turd rebel turd burglars. For me, it's his transional scenes, from innocent Ani, to wicked Darth, which seem the most drama filled.
His humanity, and therein his loss of it, is more compelling than random murder.
I can't count the "unofficial" version when comparing.
As far as anakin turning to darth vader, it was pretty poorly acted, which takes everything away.
There is a big difference in a petulant child killing little kids and mindless creatures versus numerous grown men with weapons that have absolutely no chance of defeating him though their lives and the universe is depending on them.
That scene is on a whole other level.