WARNING...check out the MIDI capabilities first, they don't necessarily make good MIDI controllers. Look at the detail data list to see exactly what MIDI messages are sent from which ever kbd you are looking at. Check to see what if any MIDI msgs are sent from various switches, knobs etc that you want to use.
If all you want to do is send MIDI note messages, pitch and mod wheels control msgs......no problem.
All I need is: keys, pitch / mod, octave and transpose. All PSR-S / Tyros transmit that.
Just need to find one with mod and pitch wheel that’s pretty thin, and not to pricey.