Not really a full blown arranger.( only 2 variations), and of course heavy.
Wait for Korg Xe20 ( still not full blown but 4 variations, basically EK 50 with 88 keys plus additional piano sounds and super light with speakers).
http://www.synthzone.com/forum/ubbthreads.php/topics/488548/Re:_New_Korg_arrangers_-_i3__a#Post488548
http://www.synthzone.com/forum/ubbthreads.php/topics/488548/Re:_New_Korg_arrangers_-_i3__a#Post488548