So you're looking for a MIDI controller as opposed to a synth? What price range? "Intelligent Keyboard," I think that term is somewhat passť these days. The "weighted keys" is a little tricky. You'll find some saying weighted and others saying semi-weighted and if one is used to a real piano they may not like the action on either. It's really something to go to a music store and feel. I use an Axiom 61 from MAudio. I think it might still be the best bang for the buck out there. The keys are semi-weighted. Does it feel like a real, even only decent, concert piano? Absolutely not.
Not that it really matters but what software are you planning to use with this?