I have mine installed but not on the road as of yet.
Install is pretty straight forward with decent welding and fab tools.
As far as if its worth it? People value things differently.
I have the street linx kit. Install was straight forward. I welded everything on the axle instead of having bolt on brackets. I love it and the car isn't even on the road yet...
Our club used the AlterKtion front and Street Lynx rear suspension on our charity project car in 2008, a '68 Valiant with a 400ci big block. Car handled every bit as good as a new vehicle.
Only you can make the decision if it's worth the money.
You can check out the build pics at our club website, www.inlandmoparscarclub.com
its a pretty easy install. a little time consuming though. miminal welding but that welding is important so if your welding are the slightest bit questionable hire someone to do the welding. you can set it all up pretty much and have the guy there to weld it a minimal amount of time so it really shouldn't cost much if ya have to hire some one...
the system even though designe more for handleing dropped my 60' time from 1.69 to 1.63. around corners its night and day. incredible man. the only slight draw back i have is with the new baby and all her **** in the trunk with my tools, jamie and my 14 year old the rear sags more then say leaf springs would. but seriously it really wasn't designed to be a grocery getter suspension. i'll probably just put the size up springs on it. but with just me and my sone in th ecar and none of the baby crap the back sits right where i want it and rides and corners great. it feels like a modern car.