Tnx.
I've been using it for two months. I agree with you. Many things show issues after a longer period.
There was one minor update to the Carsifi app (not firmware for the adapter). After I set it, it simply works and I didn't have problems with it, except for some disconnections in the same places. I "found" two of them - circle cca 50-100 meters, where it simply disconnects while driving. But it reconnects back very quickly without any intervention.
Conclusion: I'm very happy with Carsifi as you can read in the review.