AZ requires at a minimum policies be issue-age priced - which rules out attained-age - so you are pretty much comparing apples and apples, although it isn't a bad idea to check history on rate increases. Issue-age is generally more expensive initially, but rate increases once policy is purchased are limited only to inflation, not age and inflation.
An exception to Issue-Age in AZ are S-USA Life (never heard of them) and AARP UHC - both of which,
per Medicare site, are using community-rating in AZ. UHC has recently revamped its pricing structure for community-rated policies. Provided you are recently eligible for Medicare (within past ten years), you should be seeing better prices to age 81. After age 81, there are no further price adjustments due to age - only inflation.
You can still price UHC policies online, here:
https://www.uhcmedicaresolutions.com...ent-plans.html
This tool isn't always available - seems to disappear later in the year.
Also, look at Medigap N. Doesn't cover excess fees, but Mayo in AZ - which charges excess fees - isn't taking new Medicare patients, anyway. The very limited copay factor on N often results in a noticeable premium difference if you are willing to forego excess fee coverage.