Each has its own merit. I like the SD40 because of its portability and of course it's realistic drums/percussion sounds.
What I love with the PA1000 is its completeness,everything are there, vocal effects/harmonizer, powerful built-in speakers, songbook and deep in customization.Sounds are great too with minimal tweaking. What I love with E-A7 is its weight, live sounding, usable styles, easy to use,expandable,and lots of real time controls like sliders, knobs. It is cheap too.
But He was wounded for our transgressions, He was bruised for our iniquities: the chastisement of our peace was upon him; and with His stripes we are healed.
Korg PA1000, Roland E-A7, Ketron SD40