I liked the Niuweidao a lot, after holding on to your +3 one for a little while when you were gone Tydeus, I noticed I could stomp in melee pretty bad even with barely any PS, when I was leveling a 1hand cav hybrid. Later on I was doing a 15/24 agi shielder/polearm hybrid, and focusing on hunting archers and stuff for a change of pace from being a cav lance griefer or 2handed greatsword hero.
I found the Niuweidao to be one of the best damn 1handers in the game for sure, and I was able to abuse its high speed in ways I can never do with a longsword or katana, though to be fair I haven't really tried the katana too much, as a 2handed sword without a stab (might as well not have one) you lose too much utility imo.
With the Niuweidao, I was able to beat a ton of other melee, especially shielders and even decent ones, by abusing the ever living shit out of left swing circle strafing spam. With high athletics, its really hard to have the presence of mind, footwork, and reaction time to effectively counter this kind of weapon while facehugging. A quick overhead after blocking a big strong 2 hander is usually a free hit with that thing too.
I eventually traded it away though, because I found the reach too limiting in a lot of situations. Namely, even with pretty low armor weight and 8 athletics, I would be able to get at most 1 hit in on an archer before they accelerated out of my reach, which pissed me off to no end. I probably would've had to switch to peasant clothes to be able to use it to hunt archers, but I like fighting in groups too and you just can't do that with cloth (because of team wounds of course). Maybe if I worked on right swing abuse more I could've adapted too, but meh. So I gave up and switched to elite scimitar for that gen
And I honestly think the elite scimitar is the stronger weapon, but the niuweidao is better for 1 vs 1s in melee. I should've tried it with maxed weapon master, I bet then it becomes one hell of a joke.