I used to have a BM hunter. A lot of times on trash I would Serpent Sting before I started spaming my SS macro. Other than that, its just spam that one button. I don't know how mana was in raids cause I never got to raid with him, but in 5-mans, I would go through my mana in like 2 minutes WITH Aspect of the Viper up. Then again I only had about 6500 mana at the time...So yeah, if I knew the fight was gonna be about that long, I would only use my SS macro. Hell, I never clipped my shots without the macro when using quartz, but I only got it for the ease of using KC and being able to cast SS all in one button. Its not hard to not clip your shots.
Shhh! Theres a dead horde in my trunk. Wanna see it? Fuck around and you'll be it.