I like Nightstalker, but it isn't because one is better than the other. Nightstalkers are great for trapping, I mean, walls of flames, supers that anchor characters to them, smoke that makes it hard to target people and can be used to force people out of hiding, they're set to seize people's movement. Bladedancers are cool, but I don't like the risk that comes with flinging yourself into the enemy to use your super. Blink Strike can OHKO sometimes, which is great, but when that fails, there is a slight opening, and hunters are really fragile. Their grenades are purely meant for damage, they aren't super versatile. I always like Void Grenades (Postmortem kills forever) and they don't have those :( Personally, I choose Nightstalker, but again, it's all a matter of preference.