Well since we can have any car we want (because the cost is not a problem9, we'd take the fastest car. THen there's no point in making 2 or 3 cars of the same class. Unless they are balanced out to be roughly equaly fast. That's why the FZR has an H pattern and has mroe balast than the XRR and FXR.
Regarding the boxes, have no idea, just read somewhere that Porsche's sequential boxes are insanely expensive.maybe it's down to more or less being merged with the diff because of the position. That would make it a lot more complicated inside. We need tristan or someone alike in here, fast!