Other than aesthetics - why? - Planning on serious engine modś?. If so I suggest the PIPERCROSS route with
@Claviger bellmouths inside.
The issue of left knee rubbing the filter is one to be aware of, especially with footboards. Apart from filter damage - your inside left knee will be black and oil covered.
And be aware the emissions tests in Spain have just been made EVEN more difficult to pass. Received the alert yesterday.