Thanks so much! This info is incredibly helpful!
My system is rather old actually. I’m running an Asus Laptop from 2009. Some specs: i7, 4GB DDR3, Nvidia Geforce GT240m, Seagate 256GB SSD. The preview is very laggy and I tend to have to use Shift+B and sections just to be able to see the playback smoothly in the preview window.
How much more smoothly do you imagine the preview playback will be using the other codecs you mentioned rather than MP4?
Thanks for your help Aaron!