Can it really offer those views? Last time I tried it, it seemed very, err, bare/unpolished. Kinda felt like Arch Linux, I don't doubt it can't do it, but I don't know if I can do it without reading some documentation (no disrespect intended to Arch or Sumatra!)

Sumatra can do side by side with or without a cover page but I don't think you can do a frameless UI and the dark theme is a bit fugly.

It is a fairly mature program, it's just that the developer decided to maximize on "small" and "fast" at the expense of other things.