For those of you who demand the utmost steering response, for whom DEFCON bushings fall short, there's the H2Sport spherical bearing kit:
Instead of using rubber bushings, the kit uses solid bearings, eliminating any unwanted play in the front control arms. This improves handling, though it also increases noise/vibration/harshness transmitted through the steering wheel since there is no longer any isolating rubber in there but instead just a solid bearing.
I don't have any experience with them but from what I hear they perform even better than DEFCON adapters and Mk1 bushings, although the DEFCON setup is considerably cheaper (~$160, see my post).
For those that demand the best performance though, the spherical bearings look like a good choice.