I have MGUS and also considered an Advantage Plan but decided to stay with original Medicare+Medigap for the following reasons:
Once you are in an Advantage plan and decide you want to go back to Orig Medicare+supplement after one year, you will most likely have to go through underwriting with new Medigap insurer and they are under no obligation to accept you based on diagnosis and past medical needs.
2. Many Advantage plans have PPO plans where you can go to any doctor within their network without a referral (unless specialist requires a referral from GP which many do) however, this will necessitate making sure that each doctor you are referred to (including pathologists who read lab studies) are in network or you will pay a higher out of network cost.
3. There is a co-pay for most services including doctor visits, tests, ambulance, hospital etc so it can add up.
4. Most have a catastrophic out of pocket limit around $6500-$7,000 per year however that means if you ended up with a serious condition and had to pay a lot of out of pocket let’s say in December and then had more out of pocket expenses in Jan due to illness or accident you could potentially be spending $14,000 in a period of two months. (But then your catastrophic out of pocket limit would be paid for the rest of the year )
My husband and I have Mutual of Omaha plan F and pay around $146 per month each (I know that varies by state) which covers the Medicare annual deductible so we never have to worry about out of pocket costs unless it is something that Medicare doesn’t cover.
They have 100% US based customer service which is a HUGE factor for me as I absolutely hate calling the insurance company and taking with someone in a foreign country with an accent I can’t understand and hearing their kids yelling in the background or dogs barking while they work from home! (I am hard of hearing and accents make it more difficult for me to understand)
Hope this helps!