I've been running GrapheneOS on a Pixel 6 for well over a year with few issues. i DO use sandboxed google play services and all apps i've needed so far work perfectly fine.
I found the official installation manual to be very clear, especially if you're somewhat tech-savvy. The only thing that was less obvious at the time was installing the Sandboxed play services but i believe they have since made this easier.
I upgraded to a pixel 7 recently, ONLY because of the camera, unless you have specific demanding apps you want to use wouldn't worry about performance, it was very fast for all daily tasks.
Hope this helps