BMW seem to be able to manage the MINI brand quite effectively despite the wails from some quarters. I don't see why this won't work either.
The comparisons with the Vanden Plas was not the VP, it was the Allegro. This MINI is based on a sound platform. The similarly-themed ones from the 60s were not Vandens Plas, but were a much different animal.
I'm no great fan of BMW, but sound engineering and design deserves its plaudits, and these I'll happily give. I hope it does well.
What I was reminded of straight away was not the VP, but the forthcoming DS3 from Citroen. Maybe that is pitched somewhere between the MINI and this custom version.