I had the keystation pro88 for a while. It has weighted keys but no graded effect which means that the keys are the same weight from bottom to top.
The only thing i didn't like about it was the way the keys are made. They are not in one piece. When you play you can feel that the "hammer" part is always in a distance from the plastic from which the keys are made, so when you play faster parts you will press the key and feel the inner part of the keys coming back AFTER the plastic part of the keys.
It does seem a bit weird but the second you lay your hands on you'll see what i'm talking about. One more other thing about the keys... they are much more harder then keys on stage pianos, and they are deeper so it takes a while to adjust. If the keys weren't made out of 2 parts that would be good for dynamic expression... but like i said... it's not. But then again... it doesn't cost much so i guess it's ok when it comes down to money
There are LOADS of sliders and assignable knobs so that's very useful.
oh, and one more thing... the keyboard is heavy as hell! So prepare to pump up your muscles
