mini cooper d clubman

[cooper2000]

my other 1/2 has purchased a few mini coopers over the last few years and is looking at changing to a cooper diesel clubman - the car is an ex demonstrator with chilli pack 8 months old with a few thousand miles on the clock they are after £14600 and will give us £10200 for a cooper petrol nov 07 with pepper pack and 27000 miles on the clock.
Is it a good deal?
Is the clubman any good?
Is the desiel engine ok?
How hard will it be to resell on and how much do they depreciate comapred to the petrol cars?