Alexxx,
very good appraisal by Jamman.
Apart from the piano sound there is NO reason whatsoever for going for the Roland at the expense of the PA-50.
I have owned both PA-80 and PA-50 and worked and programmmed with them extensively and the PA-50 is 95% identical with the PA-80. (it has no afer touch, and no mike input for example).
But sound and style wise these two machines are identical.
I have said this on many an occasion, money wise you don't get ANYTING better than the PA-50 !!!
good luck anyway.

john