I have tested all free Android variants (and debloated a few horrific proprietary ones) and GrapheneOS is by far the best, yes.
Very robust and reliable base, significant work on security unlike any other project. Not very shiny on the surface, but apps can be replaced and GrapheneOS is perfectly compatible with any Android app you wanna use.
Hell, I am administering a poor system that runs like all the big tech apps there are, daily, and it works fine!