Was wondering what the main difference was between Asymmetrical and Symmetrical?  Also an example of when to use each one?

I'm curious also considering people say all balls are asymmetric when drilled

They are, but to the best of my understanding asymmetrical bowling balls still have a higher degree of asymmetry after drilling compared to symmetrical balls after drilling. There's still a significant amount of difference between the two. Like a ball with 0 mass bias doesn't simply equate to one with 0.020 mass bias after each are drilled. They both gain more asymmetry, and the asymmetrical is still as far from the symmetrical as it was when undrilled (assuming similar drillings of course).

Sorry if the tone is antagonistic. I've heard this a lot and it's a bit of a pet peeve of mine. 

Main differences are drillings and the hook zone on an asymmetrical is shorter than a symmetrical.