The 8000s keys are a bit heavier feeling than the 3000, but not significantly. Much of the key feel has to do with the mechanics of the rubber strips, and where they are positioned in relation to the key's pivot point. The closer they are to the pivot point, the lighter the touch. Some folks compar the 3000s key feeling to the Tyros, but IMO the 3000s keys have a slightly lighter touch.
PSR-S950, TC Helicon Harmony-M, Digitech VR, Samson Q7, Sennheiser E855, Custom Console, and lots of other silly stuff!
K+E=W (Knowledge Plus Experience = Wisdom.)