Hi DrVenture,
I have Plan G, but I know a bunch of people with Plan N and HD-G that are very happy. I am going on my 5th year on Plan G and because my health has been good, I could have saved +- $30/month on Plan N and significantly more on HD-G. But as you know, this is the way insurance works.
Personally, I would only go with G or N, but I have seen many numbers where HD-G may be the best deal; financially. There are few differences between G and N, co-pays up to $20 for an office visit (could get expensive if you have cancer and need multiple chemo and office visits weekly), $50 for the ER if you don't get admitted, and what is know as Part B excess charges (Google that). I know a number of people who have Plan N, love the savings over G and have never received a bill for excess charges. I want and have Plan G, not for today, but when I am 90 years old. I don't want to be thinking about copays or deductibles (beyond the annual Part B deductible). Also, like yourself, I can afford Plan G.
The Bogelheads forum is your best to read and post on the subject. Volumes have been written there. Also, search for posts by or including ModifiedDuration. He is the resident expert and you will be able to exchange private messages with him. By the way, he has HD-G with United American, who I understand are the leaders with HD-G plans.
I hope this helps.
February 26