I love the animation for it, but the damage is pretty horrible. Not even Buster Plus can fix that one.
True, but it makes it all the more sweet when you kick X's ass using that alone.
Other than that I pretty much just use it as an anti-Taxi weapon. Funny, though, Shot Eraser/Black Zero effects apply to the Z-Buster the same as they do the saber, so you can cut through X's shots with that little pea-shooter.
Inversely, X can destroy Zero's shots with Gaea Armor. But you're REALLY asking for trouble if you try that against Awakened Zero, since his shot delay is determined by when the previous shot pauses and not by timer, thus destroying them outright will cause him to launch the saber wave instantly.
Hyper Dash translates to dash-jumps pretty well, particularly when fighting enemies like the Nightmare Mother where precise jumping is needed (especially in Extreme mode). Speedster is better when you need to clear pits, like the one in Metal Shark Player's stage, for instance.
It depends on your method. For maximum dash-jump distance, you want Hyper Dash and Jumper; Speedster is irrelevant. Speedster aids in those who prefer air-dashing for whatever reason (which I suppose is valid if you're Mach Dashing or Nova Striking your way through, although the latter pretty much gets you where you need to go by itself), and in weapon-physics-exploiting.
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