i had the same BBS RC's on my audi.
iirc, weight isn't too bad. 19-21lbs? the RC's are cast. the hub will sit fine since VW CB's are 57.1mm, while subies are 56.1mm. though one thing that might be of concern is that the GLI BBS RC's are ball seat and all
12x1.25 lug nuts are conical.
just to be safe i'd run cone seat -> ball seat converter washers from BFI.