I think the cost is probably the largest part. Some people are leery of Afrezza because we don’t have long-term history of people using it. While there’s no reason it should cause any problems long-term, we don’t have the history to back that up yet.
There are quite a few people that use it on this forum though. I think @TravelingOn’s partner, @MM2, @CatLady, and @Sam are using it. I’m trying to remember who else.
Here’s my thread from when I started: Afrezza & upcoming endo appt
It’s a year old though.