About the XJ, me too i wanted one, had a look at more than 15 cars all over the UAE, but could not find a clean and well maintained one. They were all pretty run down. If you you are lucky and find a good one i think its a great car. not a lot of electronics to fail, easy to repair, plus they are cheap so even if you have to repair something you have budget left for that.
(I am talking from my experience as I always drove pretty old cars. Cant talk about the XJs offroad capabilities as i never had one and also newbie in that field)