They are worth the upgrade not just for the peak rwhp, but the powerband. I haven't dyno tuned my car yet so I can't give you any numbers. But as Mark said my car definately gaines some mph in the 1/4 even untuned. The good part is that the power doesn't fall of in higher RPMs anymore. And I can feel some additional torque earlier in the RPMs so the car feels more driveable.
Its pretty obvious that my car is breathing a lot better with the cams just looking at the newer timeslips. So I'd say those cams are worth it.