That's how I felt at first too until I maxed my discipline. After that the voidfang vestment lost it's luster and the nothing manacles have been my go too. Scatter grenades are just harder to use but once you get the hang of it I think nothing manacles are probably better if your using a voidwalker. Axion bolts are still the best though. It just sucks that I can't have two of them. It really just comes down to how you play.