Kylo Ren, it's not even close imo.
Discuss.
Edit: No EU lightsabers
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Okay, who honestly likes the Inquisitor's sabers? I mean really. Most impractical design ever. Sure, you don't have to actively block blaster bolts that much when it's spinning, but when it's spinning it's almost impossible to wield effectively. Not to mention it would increase the inherent risk factor by several orders of magnitude almost to the point of rendering it useless out of how immensely stupid it would be to try using.