What's the best stock 4x4 system for snow?

I'm looking for a 4x4 car that will excel in snowy conditions.
I've had a '91 Jeep Cherokee, a '97 Jeep Wrangler Sport and a '01 Land
Rover Discovery II.
All of them were equipped with stock 4x4 systems, and none of them
impressed me when it came to deep snow capabilities (not so deep that
they landed on their bellies, though. I know that no car can keep on
moving if all four wheels are in the air...).

What I'm looking for is a 4x4 that without modifications are built to
eat through snow with all four wheels turning.
I've heard that the Mercedes Geländerwagen might have the best stock
4x4 system with diff locks both front, rear and central, but I'm not
sure.

Can someone point me in the right direction?

And please: I'm looking for unmodified drivetrains - I know I could
add aftermarket locks (ARB etc.) to my Jeeps but I'm looking for the
best unmodified 4x4 vehicle for use in snow...


Best regards,

Christopher
Oslo, Norway