For me, the only reason to upgrade to El Capitan (10.11) is METAL. If you're running any type of Pro-App- you should benefit from the faster graphics performance. However, if you're running a Mac older than 2012, it will not be compatible even though El Capitan could be. 

 What is METAL? This is what Apple's says, 

 "Metal is a new graphics core technology that gives games and apps near-direct access to the graphics processor on your Mac, delivering enhanced performance and a richer graphical experience. Metal speeds system-level graphics rendering by up to 50 percent, as well as making it up to 40 percent more efficient. Metal allows the main processor and graphics processor to work more effectively together, boosting high-performance apps. And Metal is designed to be great for games, improving draw call performance by up to 10x and paving the way for new levels of realism and detail.”

I am looking forward to using Motion 5 on El Capitan with Metal. I will be posting more about my findings once I make the jump.

To learn more about Metal- see Apple’s developer video here:

https://developer.apple.com/videos/wwdc/2015/?id=603