I installed the Poly Trackbar Relocate and Drag Link Flip yesterday. It was an easy install. I used a 7/8" Unibit with a drill bit extension to drill the hole for the insert above. It cut the hole easily.
This is a definite improvement (in driving) over the FT frame-side trackbar bracket with dropped pitman arm. I also have the Poly Tie Rod, so my steering is feeling pretty stout now.
I have 3" of front lift and the axle is pretty well centered with the stock trackbar and Poly kit.
In terms of driving comfort, I'd rate it this way (for ~3" of lift):
1) Poly Steering Correction Kit (trackbar axle bracket and drag link flip)
2) No trackbar bracket, adjustable trackbar
3) No trackbar bracket, stock trackbar
4) Frame-side trackbar bracket, dropped pitman arm
ps - the dropped pitman arm puts way too much stress on the steering shaft and box. You can really see the box moving back and forth under the hood with the dropped pitman arm installed.
'08 JK Unlimited Rubicon