Hi.
The v8 is really just the same as any other engine, except they really like frequent oil changes so service history is important, i do mine every 3000 miles, and they dont like cheap ignition leads. It should warm up fairly quickly, say 7-10 mins to hit the middle of the gauge and stay there. There should be no rattles from under the bonnet and the only thing i would add is that it should go up and down smartly if all is ok with the air suspension. If you've not owned a classic and this is your first Range Rover and V8 hopefully it will make you smile like mine does when you get the chance to drive it properly on or off road. Oh and make sure all the warning lights go out for Abs and traction control as they take a few yards.
Cheers, Nick.