Best ifs kit? rms, hdk, gt suspension, or magnum force?

Ideally, you would design the set up differently for every build based on the vehicles specific ride height.....just not practical

Or...have one ride height spec for the suspension specs.....like the factory. But then it is "one size fits all"

The compromise for me are the different models of k frames based on the builders ride height expectations I move the LCA pivot....along with everything else in 1/2" increments.

Luckily....most fit within a standard 1" range....but the slammer models are moved significantly.

You are very astute.