Is it better to have one big SSD with Windows + data, or to have a smaller SSD for Windows and a large SSD for data?

You will like this one.

The major concerns with how to setup your computer's drives falls into lots of categories based on lots of different use scenarios. What type of computer you have, what kind of software you are running, your OS, and exactly how much data you are using, amongst others, will all be relevant factors here. This answer will try to parse out a general average…