I just finished demon souls and I thought it was pretty good overall. I felt like the difficulty was interesting. I hit an initial wall until I realized I had to jump from area to area. At that point I steamrolled the rest of the game in two days.
Not my favorite of the souls series, but it was interesting. I could see how they used demon souls as a way to test the waters with various ideas.
I still think my favorites are dark souls 3 and sekiro.
Currently playing bloodborne now. I like where it’s going, but I’m still only on the third(?) boss so I’ll have to wait and see. It’s the last of the series that I need to play.