You don't need 31inch tires if your car is having portal axles (portal hubs).
Land Rovers are pretty good thought still not in the same class with Volvo's old C303, Pinzgauer or Unimog.
Pic of Pinzgauer 6x6 showing its rear
portal axle.
For offroading I'd take C303, Pinzgauer or Unimog over any overweight Hummer... Those are too big and heavy (IMHO of course).
They don't have leather seats or electric windows or air conditioning but you really don't miss those when you're stuck in a deep mud in the middle of nowhere
