Amazon has the 5 star bars.
You can get a lot of high end chocolate pretty easy where I live. The 24-hour Korean places usually carry a good selection. So I'll go by what's easily available there, in terms of availability. I prefer dark chocolate. These are the bars you eat piece by piece usually and not the whole thing like a Kit Kat or Snickers
Chocolove is excellent
Lindt is very good and widely available.
Paul Newman's Dark Chocolate with Espresso
is great. They make good peanut butter cups too.
If I was going by regular drug store or candy store candy, I would go with some of the new M&M dark chocolate flavors. I really like the dark chocolate mint ones.
I also know someone who got addicted to the Coconut ones for a while.
When I was kid I used to vacation in this town where they test marketed mint M&Ms, but they never brought them to market anywhere else. Now decades later they have, just after I stopped eating sugar for the most part.