Range Rover/Defender/Dicovery question (no Nonspecific Forum)

Would any Land Rover, still in good condition, new or used, be able to do tough off roading, from rocks, to sand, to snow and mud, to water as high and deep as the hood of the engine? THat last one keeps me puzzled, 'cuz I'd expect you'd need to have a snorkel for that, unless the Land Rovers can do it, and I think they can but I'm still not sure. I saw a video, of an old Range Rover, able to go into water as deep and high as the hood of the engine, and this was on their website. THose Land Rovers that do that, are they at all modified, or are they both pure Land Rovers?

Here's the vid by the way.

http://apps.us.landrover.com/lr_videos/RR_History_420x165.wmv

Most are pretty much stock. The most common "mod" done to them is a locking differential and maybe some more aggressive tires. As for the wading in water thing, the air intake on rovers is usually towards the back of the engine (where water has a harder time getting to it) and it is up as high as possible. That makes for some pretty deep wading with a stock truck. Many people do put a snorkel on though to lessen the risk of water gettting in the engine.