My Minnesota BCBS plan is Senior Gold. I got it before they stopped covering the Part B deductible and was grandfathered in....but that deductible is only about $240. Check out the Medicare site to compare Medigap plans and their costs in your area. It is an excellent tool. Each plan has a letter so that one can compare "apples to apples".
I would never change my Senior Gold plan now, I was so happy I had it when all my health issues started. But each year I check my Part D drug plans to see which is cheaper. It is an easy thing to do. One puts in one's drugs and it pulls up all the plans one is eligible for and gives costs for each plan. I am used to computer tools because of my previous work...and Medicare has a great tool. They also answer the phone calls promptly.