4ePikanini really answered this already. The big difference between the body lift and suspension lift is the center of gravity, suspension lift lifts the frame, engine, gearbox, transfer case and body higher, body lift only lifts the body higher. I plan on doing a body lift at some point and removing the suspension lift. Another advantage with the body lift is that it creates more space for the fuel tank, either to lift it so it's more out of the way or to fit a long range tank.
I'm not in complete agreement with the body lift necessarily being easier and cheaper, I think a small suspension lift, say 40-50mm is can probably be easier than a body lift and around the same price. That is putting blocks under the coils and adjusting the torsion bars. This type of suspension lift will rob you of some articulation however.
A body lift of around 40-60mm is also easy and cheap, just need the blocks for the body mounting points and longer bolts. You will have to jack the whole body up to fit them. As I understand it brake lines and steering will tolerate 50 or even 60mm lift without problems, just watch the brake lines while you jack up the body. There is built in slack somewhere, a coil of brake lines that can be utilized. The problems you'll have to solve are:
1. Radiator probably needs to be moved down, since the engine and fan will move down compared to the body. Radiator is mounted to the body.
2. Hole in floor for transfer case lever needs to be enlarged backwards, since the floor will hit the lever higher up and stop it getting into 2H.
3. Bumpers are mounted to frame and will have to be moved up to preserve the look of the vehicle. This means modifying the bumper mounts.
My reasons for wanting to switch from the suspension lift to body lift are that eventually I want to go to 38" tires. In the meanwhile I want to do a couple of modifications that require the body lift or that I would have to redo after the body lift. These are fitting of a receiver tow hitch, front and rear and enlargement of the fuel tank. In the rear I want the tow hitch receiver to exit through the middle of the bumper, where the hitch is now mounted, so that's dependent on the bumper height relative to frame. In the front I want the hitch to exit through the middle hole in the row of holes under the number plate so same thing there. The receivers front and rear are meant for both bicycle carriers, on rough roads they are better kept on the front since the Pajero is already long enough in the rear

Also they are eventually meant for a winch, that can then be used either front or rear, depending on what kind of trouble one gets into.
In my case I also want to move the whole body backwards by a few cm to create more room at the back of the front wheel well and then move the rear axle backwards to create more space at the front of the rear wheel well. These are the trouble points for really big tires, the doors are not easy to modify. This will mean welding new body mounts to the frame further back than the current ones and they will then be made higher so blocks will not be needed. This is much more involved but ends up stronger and people have fitted up to 44" tires to blister fenders this way.