What's the your best experience with a CI system with code on GitHub

I'm evaluating CI tools for projects hosted on GitHub in a medium-sized enterprise. Looking at CircleCI, Jenkins, Bamboo, GitHub Actions, and Buildkite.

Since GitHub Actions is the default option, everything else is essentially being compared to it. But none of them really stand out—most have some limitations when working with GitHub, while GHA itself feels pretty barebones, requiring extra work to build out missing features (like proper test reporting).

For those who’ve worked with CI and GitHub, what’s been your best experience? Any lessons learned or recommendations?