Well...I'll try to help. I don't really know the particular keyboards that you mention. Polyphony gets important if you're going to do multi-layered MIDI work on your computer with lots of different instrument voices. If you are limited to 32 note polyphony you can only have 32 notes sounding simultaneously from that keyboard. (It's NOT the same as "multi-timbral" which essentially determines how many different kinds of instruments you can use at once.) And it gets tricky because some instruments (like piano) use up two or even four "voices" to play a note, as far as your computer is concerned - to produce a dense, realistic piano note sound. Having said all that - 32 note polyphony is PLENTY for solo piano playing and recording. There might be a few THICK Rachmaninoff piano pieces where you would hear notes "dropping out" as you hold down the pedal to sustain complex groups of chords. But for MOST piano music youve only got ten fingers and holding that pedal too long turns to mush pretty fast anyways - unless youre Barry Manilow and youre just trying to make the young girls cry or something. I had a Yamaha CLP-250 for years that only had polyphony of 16 and it WAS an occasional nuisance at that level but actually pretty rare at 16. Bottom line, in my humble opinion, get the keyboard that feels and sounds best to you (and your budget). 32 voice polyphony is fine unless youre planning to get into recording New York Philharmonic sized orchestral scores for George Lucas's next installment of Star Wars.