Just curious, but why the need for more polyphony?

Are you running out of voices?

Or is it one of those stats that are easier to quantify than sound quality, or ease of operation, or quality of styles, and thus makes it to the top of the list?

Me, I'd shoot for better D/A's, if you want to find a factor that is never discussed much, and manufacturers rarely publish specs on. It would probably make more difference to your perceived impression of the PA2Xpro's overall 'quality' than a few more voices of polyphony, IMO