I didn’t upgrade: I created a new volume and installed a fresh Catalina on it. Honestly it’s been working great for me and the battery life increased (probably because my old install was… uhm… dusty)
Yeah, I do this every time there is a major OS update and it saves me a lot of hassle. It also forces me to re-evaluate everything I had previously installed. Usually I end up with a much cleaner, smaller, and more optimized image. It also trains me to get very comfortable testing backups and restores and knowing how to quickly recover from any problems.
Thanks for this idea - I've been holding off on upgrading, but I would be much more comfortable installing on a new volume and migrate instead of upgrade.