I am paying for Kagi. Has worked well and some searched topics had been human curated so the answers are right there in the results. But it also does a good job with obscure searches, although it seems it tries to alter the meaning or context in order to show more results.

Best feature is the ability to hide from the results removed sites like Reddit or Quora.

So? Vivaldi is FAR superior to any other browser, even Chrome engine base ones. With the amount of customization, privacy and full Chrome plug in ecosystem support, being close source is hardly relevant.