I would love the ARX too, but A.) its expensive, and B.) they wont make them. and #2. my yamaha motiff xs88 blows my Roland G7 out of the water...
I have 6 boards i use.
I just bought both the yamaha and roland G. played with them extensively. To the bear ear alone in my gigs, at home, on stage, the yamaha just FEELS right. I love the Roland G7 for looping, and synth sounds, but for those that just have 1. I hate to be biased. I like my yamahaa xs88 better. In fact though, cause im giving up waiting on arx, im buying Srx, world collection, and then 2nd either Orchestra, Dance, or trance trax for my 2nd expansion board for roland G7. Srx is good enough for me. Make the sounds work for you, forget about ARX.
my boards
1.Yamaha dx100

i use for sound effects, water, thunder, lightning, etc
2.godfather Korg M1
3.Kurzweil x2500. 88 keys, hate it. worse board i ever bought.
4.Roland Xp-80, still use this alot
5.Roland fantom G7
6.Yamaha motif Xs88
Paul Christopher