While I agree function over form has a place, most of the design that goes into cars is form to sell. I've got the 2.5 so I don't plan on breaking the sound barrier just yet. But I've always liked the roof wings on drift cars and wanted to do something different.
Anyways I gave it a go and am pretty happy with the results!
My first two rounds of fiberglass failed, but I found that the miata wing is a good base, and with some heat gun love you can make it work.