RE: jacking points
Imagine the left side completely stuffed, and the right completely drooped. Now imagine during that the radius arms tweaking the axle in opposite directions with the weight of 36" meats on the ends.
If you don't have a lot of wheel travel and mostly plan to plow through mud holes a radius arm setup might be okay, but there are definately more versatile setups out there (Full Traction, Skyjacker to name two). It shouldn't be any harder to design your own 3 link setup for that matter either.