Has anyone had experience switching from COBRA to a NY Medicaid Managed Care (MMC) program?

Qualified for a MMC but trying to understand a couple things:

--- if a doctor accepts, say, Unitedhealthcare... is there a difference between private insurance UNH and a medicaid managed care plan through UNH?

--- Apparently not able to see which MMC plans are available to me until AFTER I drop my COBRA. (Ideally want to understand options before doing that since you can't go back). I think there's a set list based on county of residence in New York ... that right?

--- any significant cons you've realized vs. paying for COBRA coverage?

THANK YOU