https://healthy.kaiserpermanente.org/northern-california/sho...
https://healthy.kaiserpermanente.org/northern-california/lea...
The old style HMO only plan organizations are almost all gone.
https://en.wikipedia.org/wiki/Health_maintenance_organizatio...
> When HMOs were coming into existence, indemnity plans often did not cover preventive services, such as immunizations, well-baby checkups, mammograms, or physicals. It is this inclusion of services intended to maintain a member's health that gave the HMO its name.
Since the above services are required in all plans by law since ACA, there is much less difference between an HMO style plan and a PPO plan where you only go to in network providers.
UHC is notionally a PPO, but because Optum is owned by the same parent company and Optum is buying up all the providers, they're slowly becoming an HMO by monopoly. They play off of each other in any dispute.
I've had better experiences with Kaiser and had a family member who worked for them for a couple of decades.
How about Kaiser Permanente? They have been a vertical healthcare provider/insurance organization for many decades. You pay Kaiser premiums, you see Kaiser doctors, and you get your medicine from Kaiser pharmacies.