I just recently installed them on my '06 GT. So far, no complaints. I'm still working on the right adjustments for the shocks, though. I also installed the Eibach Pro Kit. It's a great combination. It's probably overkill for me, though. I can only get out to the twisties once every month or two, so most of the time I'm wasting the ability of these shocks on simple commuting, etc.
I have the adjustable Tokico D-Spec over Roush springs. Great dampers with basically 5 turns from lock to lock. I had them on the second softest setting and they were great but just turned them up to mid-way (well I was running with a Murcielago!). Here in the UK, we have roads that twist and undulate like a lumpy rollercoaster so you can't afford to go too hard and have the car bounce off bumps. I think I still need the uprated sway bars though.