For ride Id go with the Tera kit. My front settled a bit with an ARB Bull Bar and winch. The back has stayed the same. I think the RE springs are too harsh on the street and I have no opinion on Rusty's spings since I have not seen them.
I ran Rusty's for a while on my ZJ. I netted 4.5" of lift from them over stock, non UC. I hear they settle down to about 4". They ride and flex very nice, but keep in mind that you'll need to buy more parts to make it work right. You can't just spend the $320 on the kit and be done with it.
Rusty's has given me 4.5" in the front and 5" in the rear. It's cheap and great! However, get shocks that are longer than 27.5" long because my Old Man Emu LT's are too short. Shoot me an email if you have any questions.
The front coils RE uses for the 4.5" ZJ lift are snowplow springs compared to what they used to sell for the ZJs. The coils have a spring rate that was calculated for a ZJ with a V8 and heavy ARB bumper w/winch installed on the front. If you are installing them on a 4.0l, you will get over 5" lift and the ride is not that great. The old 4.5" springs had a rate of 130#/in the new ones are 174#/in (measured using a bathroom balance scale and a shop press).
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