I think the DR-880 and maybe the 660 too, they both have the ability to link several patterns, and basically do the arranger-like Variations and Fills thing with a footswitch. So instead of pre-programming the entire song, you just kick the patterns as you see fit... Just like an arranger

I definitely think that Roland, and any drum machine manufacturer, really, have missed the ball by not really porting over the arranger's system... four patterns, six or so fills to link them, and an Intro and Ending or two. For the B3 player, or anyone kicking LH bass, it would be a great product.
Oh well...
