x5 3d v 4d

[DaiMichael]

The wife is pretty set on getting an X5, which I don't begrudge so my question is, is the 4d much better than the 3d for a driving experience and which would likely hold it's value better (compared to cost the extra cost)? If we do get one it would be a cash (plus part-ex on current) buy, might be new, if not very nearly new (i.e. 6 months old).

Any idea on discounts been offered by BMW dealers for new x5's, i.e. my speced up 4d is around £53k.