GOD need to sort my proof reading skills out, blatantly read 'Supercharger' in that post but maybe was looking for 'SC' in the ad instead. Looking at it it's a Vogue....and if it's 4.4 litres it ain't Supercharged. Think the sales guy/writer of the advert is 'confundo'....as they would say in Spain....'Confused' in English speak!
Regards the 'Full Service and MOT' it may be wise to find out what it failed on...these guys will do their utmost to keep costs down. The MOT failure might be a minor thing but point to some other things that may need doing. Most garages like this 'pass' a car through its MOT without rectifying things before hand. Something more serious may be lurking underneath the shiny paintwork....I would have the car fully inspected by an independent entity(think RAC/AA do this still?) . Something like an older 'Rangie', out of warranty and bought 'on a whim'(we have all done it) could be a money pit! Go view the car at least(don't take any money with you and DON'T be persuaded into buying it there and then.....) You need to remain unemotional about this. How many 'Supercharged' Range Rovers have you looked at(physically) or driven.....if this is the first I would be very wary but go and test drive it......it will give you a benchmark to work from......but DON'T buy it if you haven't driven several others. Like I have said, there are 'dozens' out there to choose from. Take someone with you who needs to be told that you 'will not buy this car' today under ANY circumstances.....and do your research......know what things cost to replace repair and don't forget to add labour on top, even if you are a qualified LR 'technician'...
Best of luck..