Vamp wins 10/10. In MGS 2 he was dodging and blocking machinegun fire with a knife and he moved so fast the soldiers literally had no idea who was killing them until he showed off and revealed himself. Raiden was literally moving in slow motion and if it wasn't for Snake showing up, he would have killed him on the spot. He was even dodging bullets when he wasn't looking.
Plus his nanites heal pretty much any damage and Krauser doesn't have the advantage of tech or environment to help him.
And if it's MGS4 Vamp he's even more powerful going by how easily he took down Raiden.
Vamp has NEVER blocked machine gun fire and has shown the inability to bullet time, on top of that he was tagged several times by Raiden's SOCOM Pistol which is sub sonic, and was hilariously tagged by a PSG1 Sniper Rifle from across the Big Shell
Raiden beat his ass because his suit made it difficult for Vamp to read his muscle movements. When this ability is nullified Vamp can easily be tagged by sub sonic projectiles
His nano machines do heal him but even simple bullet wounds take several minutes to heal.
On the other hand, Krauser himself is extremely under whelming having only 2 on panel fights against Leon and Ada, losing both of them and I wouldn't exactly put Ada or Leon on the same level as Raiden
I would go with Vamp solely because he seemed to be a bigger threat in MGS than Krauser ever was in Resident Evil
He blocks bullets his first appearance when he's fighting the soldiers. The last one alive opens fire and he starts spinning, and you can hear him deflecting several with his knife.
He dodged Raiden shooting at him with an assault rifle while he was fully focused on Snake with him pinned against the wall.
And he's moved so fast Snake nor Raiden could keep up with his movements much less react to him.
He dodged every shot from Raiden's pistol except one which only grazed his cheek. And it can be argued he was slowed down as he did it while standing on top of that hyper oxygenated water that apparently he could move through at will.
And that fact doesn't really matter because Krauser doesn't have that luxury; his muscles are an open book. And as of MGS4, he absolutely trounced Raiden who at that point didn't even have normal muscles anymore so it should have been even harder to read his movements.
Show the exact moment where you can hear a bullet deflecting off of Vamp's knife, give me the time stamp
He aimed dodged Raiden shooting at him, Vamp could partially read his muscle movements but not fully which is why he was beaten by him later on.
This is straight from the Sons of Liberty Script
"Using a special breathing exercise, Vamp focuses his concentration. He slowly stands as if heís easing the tension in his body. The whole routine looks like the stretch exercises of a ballet performer or a dancer. // Raiden: HA! (attack scream) // Raiden abruptly opens fire. As if executing a series of ballet moves, Vamp elegantly dodges the bullets. // Raiden: Argh... ! // Like a ballet dancer waiting for applause, Vamp bends forward in a low bow. A line of blood trickles down his cheek. Vamp stands tall and glares at Raiden. He is wounded in the side. (He was wounded when he was shot by Raiden during their encounter on Strut B.) // Vamp: Ha ha ha ha... I thought so... (He sounds almost happy) // Vamp can read a bulletís course by watching his enemyís muscle to judge their aim. He is 100% accurate when judging the shots fired by an ordinary opponent. However, the pressure applied by Raidenís Skull Suit restricts muscle movement, making his moves difficult to read. This is explained via radio. // With his well-developed canines peaking out from both sides of his mouth, Vamp smiles. // Vamp: Human muscles are eloquent. They speak out quite clearly what a personís next move will be. They even tell me which way a gun is going to be pointing before the trigger is pulled. But your muscles -- theyíre different..."
No one stated that Vamp couldn't read Raiden's muscle movements, only that they were difficult for him to read which is why he got grazed in the face, if he had bullet timing speed then this wouldn't be an issue and he'd be able to dodge bullets and never get tagged regardless of weather he can read muscle movements or not
Further more during the actually boss fight, you're encourage to blind fire against Vamp because it'll be harder to hit him if you auto aim and lock on to him.
If Vamp can't read muscle movements, than anyone with a sub sonic pistol like a SOCOM could take him down, not only is Vamp not bullet timing status, he's not even aim dodging status since he can't aim dodge without reading muscle movements
In MGS4 Snake was able to effortlessly shoot him in the head because...surprise surprise...Vamp couldn't read his muscles, and I'm not sure what you mean by trounce Raiden because in their first fight Raiden, although injured, walked away from the fight, Vamp was KO'd temporarily and only survived he healed from Raiden's attacks.
I've already admitted that Vamp would probably beat Krauser, but that's only because Krauser is an even bigger joke than he is.