I considered this last Saturday. I have had my A5 three weeks and it has about 600 miles. Went to pick up my trunk hooks and saw two S5s on the showroom floor one black and one white. I asked the dealer and he said both were available. When I joked about trading, he said it could probably happen if I was willing to lose 2K off of sticker for my A5 trade. I thought hard about but then thought it would not be worth the $11K to me to do it.