I'm so sorry to write THREE comments on one article!

But having done a ton of research on Roam and alternatives, I finally decided to go with Obsidian, because your stuff is yours to keep (stored on your own computer) and there's no monthly fee, so it's yours forever. You can pay a monthly fee so your external brain is shared across all your devices, but it's only $4.99 on obsidian, where I believe Roam is more.

I just like the idea of my stuff being stored on my own device (can also back up to the cloud) not in their servers. Also accessible offline, which is important to me because I often travel to areas without internet access.