I came in here to research this exact question. I'm looking to broaden my horizons past the Massive VST, which is my main instrument at the moment.
What instrument makes the best dubstep whobbles+growls, and is it easy to control live? I'll keep searching, and check back here.

http://soundcloud.com/dapper/under-the-water-instrumental
This is my first dubstep tune, after 10 years of DJing trance and d&b here in Salt Lake City. Made in Ableton, mostly with Massive. There is a vocal mix of this tune, also on my sound cloud, but I think the instrumental is the real banger ...

Thank you! I had this same problem, and the info here helped me resolve my issue!
~bests