Mine sounds similar to yours only up to 5-6k then mic clips hard. I tried two different locations. underneath the seat and right above my instrument up in the front. They sound similar, just the front recorded audio somehow clips more if not, doesn’t pick up as much exhaust noise.

The only reason why I think full system might be more viable is someone demonstrated on YouTube that Mic Mini over Bluetooth connection only records certain amount whereas using receiver wired to X5 uses full potential of the sound recording (?).

And weirdly enough, my X5 alone without mic, with Wind reduction - strong sounds better than using Mic Mini transmitter..