I had an SD for around 8 months and covered 9000 very enjoyable miles in it. It was a superb distance cruiser and an effortless, comfortable everyday car. My intentions at purchase were to cover around 15000 miles per annum with a few continental hols. Circumstances changed (slightly) and at the time the SD had a very good residual and the GTS had just been launched.
The GTS is much more "edgy" (if I can use that youngster's term on this forum?
) and always encourages me to drive that bit too fast, if only to hear the exhaust note and exhaust pop. As above, the GTS feels lighter and does handle better (everything being relative; the SD handles far better than it should and certainly better than any other SUV) For comparison sake, my wife has a 428 cabriolet and we both feel the ride is on a par with the GTS but the handling not quite as assured (possibly because the roof has been cut off)
I guess it all depend what you and Mr Sophie want from the car? A 5 mile rush hour commute will be rubbish whatever you drive (
) but your weekend trips and 12000 miles a year will be more "fun" in a GTS if less relaxed.Residuals would seem better in % terms on a GTS especially as it has more " options" as standard compared to the SD.
mpg on my Diesel was 35+ and I've not yet seen better that 25 on the GTS (and often less than 20)
If you drive a GTS you'll probably want one!
but funnily enough I said to my wife the other day that I did miss the relaxing cruise of the SD.........but I would miss that exhaust note!
versus heart 
It's £450 annually for Years Two to Six for cars over £40k.
