I figured I'd go ahead and post a quick review of the IPF replacement headlights for the TJ.
Install was incredibly simple, remove the three torx screws (per headlight) that hold the bezel in. - this is a perfect time to paint that bezel black if you haven't already. then remove the 4 torx screws (again per headlight) that hold the headlight itself in. unplug the old unit and drop it into a trash can.
install new H4 bulb(don't touch the glass with those dirty hands) into the shiny new IPF housing. plug it in and reverse the removal. Align the headlights per Daniel Stern's site, or the instructions included with your new housing
Now for the important part. how's it light things up? Well I used Sylvania Xtravision - they are a little brighter than a regular sylvania. The improvement is much what you'd expect. It looks like double the light coming out of the headlamps. (instead of a yellow glow of light its a strong yellow beam...you know like every other car on the road).
I bought the housings from 4x4 groupbuy and was pleased with the process and shipping times (drop shipped from ARB). The bulbs came from autozone.
If you are on the fence about doing this mod, do it. Whether you choose Cibie, IPF, Hella you won't be disappointed. (personally those would be the only three I'd consider.)