The DS-10 is capable of doing 4 Drum Sequences, all of them can have notes, so its not a real problem making music with it.
You dont need a 2nd DS either, not at all, heres a good example of what it is capable of :
http://de.youtube.com/watch?v=7hh333ZfSuw
I recommend listening it till the end coz its kinda standard at the beginning
But srsly, i think you can accomplish alot of things because it gives you many ways to modify the sounds
Only Problem would be to have to be using tricks to make songs that normally wouldnt work with the standard given ways...
Too bad...
I thought somebody would be remixing with MS-10 or the DS-10...
I guess I can forget about remixing with it eh?