Just commenting on my experience this morning - 3.6L Sport mode - I was kind of in a rush, going onto a freeway merge, followed by a freeway split-exit.
Being a bit more aggressive than usual, I get up to 80Mph, with my foot on the gas paddle, not lifting, just holding speed, for a little bit over half a mile.
To my surprise the rpm was holding at 6,000rpm, steady, until I exited and lifted. I flicked in and out of manual, and could read out M3.
I have seen the rpm holding at around 4,000 to 5,000 rpm before (at lower speeds), but never at 6,000rpm. And holding steady.
I figure this is part of the PAL algorithm? Perhaps it prefers M3.