I've had them all, and still have a few old ones around including the Ketron,GEM,Roland,Yamaha,and KORG and as far as an arranger,the BEST! to date for me is KORG PA4X, great right out of the box and very tweekable, but one thing stinks about KORG,and they should change their policy, if you buy a KORG PA4X and have it for a few months, even though it's under full warranty if you sell it it considered used and out of warranty, that policy stinks, period, and I would take that into consideration next time when I buy a KORG, and this is enforced here in the US, were as in Europe a local dealer will probably still help you out.