They seem to have a number of 3 inch kits for the JK. I know that the US JK-forum sings the praises of Teraflex, but not everything that we read on the interweb is true.
I can say two things:
#1. The guys that I know and have learned to trust recommended OME to me for shocks and coils, and either Currie or Clayton for suspension components that include joints. (both of those brands use Johnny joints)
#2. It was a few more dollars, but I am VERY happy with my OME frankenlift. I am running:
OME HD coils (you will want the HD if you are running a 4 door and you intend to run steel bumpers)
OME long travel shocks (no difference on road, but a big difference off road)
Currie front upper control arms (to set the caster)
Currie rear spring retainer clips (necessary because of the LT shocks)
Crown brake lines (necessary because of the LT shocks)
JKS track bars (to keep the axles centered)
Teraflex extended bump stops
Northridge sway bar links
With all of that, I can run 35's with only the tiniest bit of rubbing in the rear at full stuff (after you tweak the pinch seam) and I am very happy with both on-road manners and off-road performance. Doing it this way probably requires a bit more thought and research than just clicking on the "buy" box online, but I think the results are great. Stan at Northridge carries all of that stuff