I have the same problem as ernesto just not as bad, its only occasionally but im not taking my chances. I've been driving it a little less than normal and sometimes only in and around town. I ordered an ACT stage 1 clutch on friday and hopefully will come in soon.
The impression I'm getting about clutches is that unless you have a street disc, meaning not a puck style disc, you're going to have a harsher, racing intended engagement. So the thing to do, for a street driven car would be to put a new street disc on with a different PP that increases the clamping force and will handle more crank HP. However, the more clamping force you want, the harder you're going to have to push on the pedal to release the clutch. Apparently the JWT PP has a close to stock feel and increases clamping force by 30%. Most ACT PP's increase clamping force by closer to 50% and on up to 100%.increase. So if a person doesn't plan to do anything in the future that entails getting to the clutch, I'd lay out my plans and figure out what I want to do with the car and how much modification I'm going to do. Then you should be able to figure out what disc you need and what PP will handle the power you'll be putting out.