Not as good as LGB’s and better than the Big Haulers.
According to reports on the German fora - BTW complete with detailed pictures, detailed test measurements etc. - the motors are substandard when compared to Bühler motors, the wiring and connectors to and from the pickups and motors is not up to snuff. The wheel sets need to be either run in or better yet, polished up prior to operation as they have some (oxide) finish that impedes operation. That should change in future i.e. blank wheel treads from the factory. (It’s about time! A R-T-R item that needs to be run in or polished prior to use? Yeah right!) Which leaves an excess of lube in the gear boxes which also hinders proper current transfer from the axle wipers.
Then there are the pick-ups which have a tendency to hang, add to that the difficulties to get the CVs to the correct trim when converting to DCC - all on account of the funky motors.
Other than that, not bad for the money - at least at the German prices. Would I buy any if they would start producing RhB NG items? Perhaps after reading all the pros and cons.

Oh BTW that BR80 steamer has the most uniquely designed drivers I’ve ever seen on a steamer - the spoke pattern is most certainly a take off on a sliced pizza and the wheel flanges fall into the pizza cutter category.
PS I guess I could translate the reviews from the GARTENBAHNprofi, to have a little counter point to the GR reviews. (As soon as I drain the swamp and provided the alligators don’t get me! :lol:)