The syntax is a little weird to get used to. I remember being really tripped out by it when I first started writing Discourse themes, but I eventually figured out how it works. It’s also possible to generate raw HTML via widget as well.
I’m not the most skilled at being able to say when to use what and where, but it’s an option to consider if you’re doing some custom work, need to write a widget, and are having difficulty using virtual-hyperscript.