Kaiser is an acquired taste. Some love it, some hate it.
From what I know, you’ll have to take more overnight calls to get a comparable income to private groups (about 3-4 in-house per month versus 1-2 from home at private groups). That said, the nature of the day-to-day work is generally easier (supervision model, less OR efficiency, less production pressure, etc).
The OC Kaisers (Irvine and Anaheim) tend to treat their young poorly. You’ll get worse assignments and call schedule. Riverside and San Diego aren’t as bad. I can’t speak for any of the LA ones.