Hi ! the reason I opted for the clear glass is also a trade off!! It is correct about the wind deflection being different from the fabric original, I would agree that because the fabric type lets some wind flow through it does not bounce back. BUT!! and here is my BUT!! the original fabric is very bad in terms visibility and for me this slight trade off it well worth it to be able to see very clearly anything in my rear view mirror.
The bounce back you speak of only comes in at higher speeds and you can off set this by dropping the rear windows.......
Having sold my old one, I used it to offset the cost of the glass one, the glass one also improves security!!!!!
I still have the fabric inserts in the headrests!!!
Always said I would go back to a 6 series