There are only 4 channels going in an arp as well...
DRUMS
BASS
ACOMP / ARPEGGIO
LEAD VOICE

say goodbye to layering and switching between OTS on the Fly

Al is spot on about the fills / intros / endings as well.
you have 6 style or "arp" variations, and you can choose which ones are intros / fills / verses / endings etc.

while you are playing a verse, u then need to hit the arp button that has a fill arp assigned to it and then u must go back to the next verse arp manually. there is no automated way of doing it.

I tried very hard with the MOXS to accomplish arranger functionality and it doesn't come close...

sound quality is the biggest attraction to the Motif series. its still clearly ahead of Tyros 4 in terms of Drums / basses and synth sounds but at the end of the day its not a one man band type device.

The closest it gets to live OMB playing is through a Midi file in the song mode. but any arranger can accomplish this as well...

honestly Donny - you will regret it. At first you'll be blown away how good the sound quality is and how far you can edit the sounds and add awesome effects - seriously!! but it will eventually sit and start collecting dust. and when you go back to an arranger it will just be a big relief!

Good luck!

Nick