Lukitoh,
Actually some drum machines will allow you to use the keyboards buttons to change patterns... I guess it really depends on what you do in a gig too... If I had $1500.00 to spend on an arranger, I'd most likely go for a Korg, something like the PA-60... Granted the Yamaha's sound good and all, but I think the Korg's are a little more road worthy.. Plus they are more in depth with the voice editing..... You could get the PSR-2000 and buy an affordable vocalizer like that digitech I mentioned and still stay in budget...

Squeak