Apple core OS work life balance

I have a job offer on the Core OS team at Apple in Cupertino and have heard conflicting takes on the work/life balance in the org.

What do current Apple employees in this group think? Do you maintain good WLB at Apple? How many hours do you tend to work in an average week? A busy week?

Since I know people will ask:
The offer is $145k base, $125k stock/4 years
3 yoe + MS