I can share almost all your assessments, FX...
I like the design and the execution as well. As you noted, the module is well constructed, with precisely simultaneous action of the retrograde minute and the jumping hours. Setting the watch reveals that much thought has been invested into the tactile qualities of the mechanism - it is smooth with reassuring solidity.
If there is one thing which I find a bit gaudy then this would be the two cabochons: while they are true to the original (in the sense that there is 'something' on the speedometer of the Mini), I felt it would have been better if the inscription of these non-functional parts would have been omitted.
I am also not convinced that the rubber inlay of the crown is a very robust solution. I heard that this detail will be revised for the final series pieces.
Overall, quite a discovery - and a promising one!
Best and thanks for your reports,