There’s two models - the Duet 3 which comes with a Snapdragon 7c Gen 2 @ 2.55 GHz CPU, and the 3i which comes with a Intel Celeron N4020. I would rather use the Duet 3, due to the cover, and since I am already familiar with the feel of the device due to having owned a Surface Pro 4, but I’d like to choose whichever works best for running Linux.
Edit: Just for additional information I’ll be using it as a note-taking tablet with xournal++, not for any heavy tasks
4 GB of RAM is enough only if you install something like Debian+XFce (not gnome/kde/cinnamon or ubuntu/fedora), and only if you only use up to 3-4 tabs of web browser at the same time along 1 more app. Basically, you will need to always be conscious about the things you have open. But it is doable if you are the conscious user type like I am. Definitely not enough for things like 4k video editing, or multiple apps open with many tabs open each. Also, always go for the x86 version, it’s better supported.