@Kobra678: They are all the same, except for Dark Berserker.
Like most Servants nowdays, mach 15 combat with mach 45 reactions. Has no-selled Caladbolg which twists space itself as it travels and was put up at city level by powerscaling.
@ReliusClover: You're gonna need to show me some proof, when has berserker done anything that makes him faster than even mach 1? Also, Caladbolg was shown when Archer says "I am the bone of my sword" in his first fight with Berserker right? At best that was building level.