The A6 has buck rogers miles on it though.
You will struggle to get a good price for it just on that basis
I personally wouldn't do that swap - your car has sensible miles on it - come the srping (if you can wait that long) I'd imagine your car would sell better being a convertible.
I've made someone a really low offer on a VX220, and with a bit of gentle persuasion he's agreed to it!