I would also have to add (please JCL correct me if I'm wrong here) that once particles get to a certain size they become slower than sprites. Which is one reason why I used sprites for smoke in my explosions.

Now this could have just been an issue with a beta-build. But it's worth checking out if you are working on particle fx.

I would also have to add (please JCL correct me if I'm wrong here) that once particles get to a certain size they become slower than sprites.

Interesting! Why is this?

I don't have a solid answer (not my part of the code, and I'm too busy to dig at it right now ) but, after running a small test, I think this may have been a beta issue that was solved.

However, I should note that the difference in speed between displaying sprites vs. particles is almost none if the sprite/particle takes up the majority of the screen (i.e. the particle is very large and/or very close to the camera). The particles probably still run faster, but you will not notice that with the overhead of so much drawing.

In short, particles are the best choice for small things like sparks, dirt, dust. When the size increases (like the cloud of a big explosion), sprites run almost as fast.