I bought a second hand Pixel 7a for my recent migration. Battery isn't great, but it's good enough to get me through a day.
GrapheneOS users tend to avoid using Google services when possible and this has a battery life cost when using apps like Signal with their own push systems. In the case of Signal, Molly is a fork with UnifiedPush support that's more efficient but it requires running a server to convert FCM to UnifiedPush since Signal doesn't support it.