I guess the resale value will be minimal on DHP.
From what I understand the big resale hitters in the UK for Premium cars are listed here-
http://www.which.co.uk/cars/choosing...resale-values/
The value of DHP will probably be lost on most 2nd hand buyers- it's hidden in the car and not visible.
If you get DHP, get it for your own use, not for any expected value come resale time.