GitUI is amazing. The only caveat to many developers is that GitUI is still unusable when you GPG sign your commits, even after so many years and with functioning PRs already created. This excludes, in my opinion, a large portion of the possible users from using GitUI. However, it might still be useful for everything Git-related which does not require creating/changing commits.
I had used it for a while in the past. The results were surprisingly good. I have moved to other search engines to experiment since then, but I have nothing bad to say about my time with Qwant.