The H1 is designed to travel a variety of vast terrain and do it at speed. IFS is MOST instances is a better option for speed and controll. The H1 is equipped with locking differentials, great approach and departure angles and 37" (I believe could be 35" but I'm pretty sure they are 37") tires to further aid in ground clearance.

IFS generally has more controll due to the fact that each tire acts independantly as opposed to a straight axle in which one wheel will act and react to what the other wheel is doing.

The advantages of the axle are strength at extreme angles of articualtion and fewer small breakable parts. With the simplicity of the design you can safely get more ride height and tire clearance from a SA without the use of drop down brackets and with it larger tires and more articulation without sacraficing strength and reliability. That's why you will see more dedicated rock crawling and mud bogging vehicles with a SA.

But with that height and tire size you lose handling and cornering stability. A desert truck at the other extreme, gets their articulation (or travel) from increasing track witdh by using longer controll arms and longer rear axles (longer wheelbase as well) thus keeping the ride height to a minimum and retaining high speed stability and cornering ability.