I moved a copy of this post to http://www.synthzone.com/forum/ubbthreads.php/forums/37/1/General_Arranger_Keyboard_Foru where you may get more results.

I use a Traynor K4 playing in the classic rock band I am in ( and I am very happy with that ) though that probably does not pump enough bottom end for a full arranger keyboard accompaniment. Because I play with live bass and drums that is not a concern for me. In fact it suits me better as it doesn't conflict with the bass frequencies from the bass guitar. Before when I used a powered box with a 15" speaker I would have to severely cut the bass frequencies to make it sit nicely with the band. The K4 has a separate summed mono output that can be used to feed a sub woofer if needed.

I just like the midrange and highs on the K4 so much better than the powered box I used to use.