Just got done replacing my RE 3.5 superflex with a RK 3.5 mid arm kit. While I can't comment on the difference in ride yet (frigging dealership has had my Jeep in the shop for 6 weeks now :furious3
I can tell you I weighed the control arms on a scale and the RK's weigh double what the RE arms do. IMO the joints are much better as well. I know weight does not necessarily mean its better, but if you put the two side by side you'd pick the RK every time. I wouldn't say the RE kit is junk but there is a marked difference between the two.
I have to say I have never seen a negative post on the EVO plush rides anywhere. I probably would have gone to them if I wasn't wanting to get rid of all of my RE arms at the same time.
Sounds liked you are ready to pull the trigger on something.
Make sure you do your homework! Don't be afraid to call one of the supporting vendors listed on this site and ask lots of questions as well. I did not do enough of this and ended up spending unnecessary money.