The first few years we were covered we used an HMO advantage plan, and it worked well, if not a bit clunky getting service. But six years ago (yes we're that old old) my wife got a lesion in on her big toe. Sans details, it took over three years to get proper treatment, which by that time became a major surgery situation with many follow-up visits to wound care.

The wife and I have no been with AARP-United Health Care PPO. The premium is not something we had budgeted for in retirement, but peace of mind is worth it. Pick our own doctors and specialists with with no referral required. No co-pays or other payment on any procedure which is medicare covered. My wife had a small lesion on her foot (same one as above) earlier this year. Her doctor recommended removal, a surgeon concurred and from discovery to removal was three weeks, not three years.
Soon my son is about to get treatment from an HMO for a problem what is clearly neurological, but what, for over two years, that HMO considered a physical problem. He had to win a grievance hearing to get this treatment.

Personally, I feel HMOs should be outlawed as violating restraint of trade laws, but that's a discussion for another time.

But in the end, get what you are comfortable with.