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

I called Denny this morning to clarify the track width measurement criteria. He said that the HDK's 58" "hub-to-hub" measurement is at ride height (not control arms drooped) from the outside of the wheel mounting surface after the rotors are installed - Not from the spindle hub surface.

If you don't have the rotors on yet, then the measurement is being made from the wrong place. Does anybody have a good measurement from the GST or any of the other brands that has been taken in this fashion? Please let us know what it is.