Basically it runs on samples - but they're actually really high quality. The main downside is It's a huge CPU killer, and it froze Reaper both times I tried it. Kind of an awkward 3 panel interface, too. Probably only worth it, if you own the machine that goes with it. Kind of a lot of money for that kind of trouble imo.
MasterHiggins, You are correct! A few cons would normally mean it's less than perfect, but here is my rationale for the 10 rating. ..
Giving this plugin a 9 rating would be too low. If there was a 9.5 option, I would have chose it! When I was in school the highest score you could get was a 4.0. Now, my nephew graduated with a 4.3. What the? I guess what I saying is this. .. . Spark offers many bonus/extra credit features that go beyond 10, minus some points for the cons. .. .