I wouldn't buy the TDv8 just to get the Park Heat, I wasn't very impressed with it last winter and the heated seats and heated steering wheel were far more effective at keeping me warmed up for the first 3-4 miles while the engine warmed up. The Park Cooling is good though on hot days!
On the basis of the poor performance of the Park Heat last winter I didn't tick that box on the options for my new car, it will have the optional heated steering wheel and comes with heated seats as standard anyway. The new car also comes with a new to LR all electric heating system (the Positive Temperature Coefficient system which doesn't use engine heat but a ceramic heater to warm the cabin - and probably flatten the battery as quickly as park heat does!) 2012MY RREvoque Dynamic Lux Plus Auto SD4 Coupe in Fuji White with full ebony interior

Mine works quite well so far an it has only run for about 10mins before i got in the car the other day

the FBH is my favorite and most useful thing on my RR, 15 minutes on and the car is warm and toasty, warm seats (takes the chill out of cold leather), defrosted and demisted glass, and also makes sure the door locks have un frozen