The most important thing we learned is to obtain a Part D drug plan from the start, because if you don't you'll pay a "Penalty" later on if you do enroll in a plan - and that 'penalty' is forever, by way of monthly premium, and grows annually.
Since we're virtually drug-free, we went with a Walmart-Humana plan that doesn't cover much, but it costs each of us less than 13 bucks a month.......in the event we require pricey meds, we'll simply swap plans during the open enrollment (switch) period that comes each October.
Appreciate the info about a Walmart-Humana plan, had not heard of it.