GMS apps work fine. The only ones that don’t work are ones that act invasively enough to notice they are sandboxed and disable themselves.
Mostly bank apps. Which is irritating, since they all have mobile friendly websites that work fine without needing to know my location and everything else about my phone.
While you can setup a second profile to put the Google services into, I don’t recommend it.
The version of Google Services on GrapheneOS thinks it has root, but it does not.
So there’s no dramatic need to setup a second profile, unless you want it for other reasons.
I personally think the second profile feature is one of the things people think they want/need from GrapheneOS, but really are happier without.
(Sure it’s safer, but GrapheneOS is already so much better than other mobile OSes - and I hate to see someone quit GrapheneOS just because they didn’t like the optional profiles.)
An exception I have seen is for apps mandated for a job. I’m happy to bury that stuff deep.
That’s a pretty good description of what GrapheneOS does with the sandboxed Google services.
I have found that the only apps that don’t work well with Samdboxed Google services are ones that work hard to invasively probe their runtime environment.
Thwy usually fall into these three categories: