Nissan Patrol Merits and de-merits:
There has been no change in the shape since year 2000 so you get the latest shape except for minor face lifting;
Very tough vehicle, i believe better off road ability than Prado three door;
Very powerful assuming you are going for a 4200;
Better sitting and luggage space than a three door prado;
New parts should be available with Nissan Ghandhra, becuase they are importing these vehilces, but finding used parts would be next to impossible.
Resale: Nissan has nissan lovers and if you find them they are ready to pay very good price for the vehicle but generally difficult to sell.
Prado merits and demerits:
Second hand parts available;
Old shape as they changed the shape later on;
Better resale value;
It will also depend on the price range in which these vehicles are being made available to you. If these are being sold for the same price then go for Nissan Safari becuase if you compare a 1995 or 1996 Nissan Safari (3 door) with the same model prado (3 door) then they have the same price range.
I think at the end of the day its your choice that matters. Best of luck.