Nightstalker is also superior in PvP in my opinion, since Blade Dancer was already nerfed.

Both supers are pretty much useless in PvP in my opinion. Arc Blade's detection is atrocious(which is a shame, i really like that subclass) and Shadowshot takes a millennia to register on people. I prefer Gunslinger, personally.

I think Shadowshot can be amazing when used at the right time, but that applies to pretty much any super. But Nightstalker is just filled with good PvP perks in general. Of course it's all about personal perference but I don't tend to focus on the Super of a subclass. I look at the overall set of perks and abilities including melee & grenades, which is why I don't really like subclasses where most of the perks revolve around the Super.