It is a lot of preparation work to do this..I have set up my XP80 with drum patterns in the lower octave. It works in a pinch but not as well as a dedicated drum machine,,SMF's can work as you mentioned[I am sure you will have glitches along the way]..I just use my G1000 now[sold the XP80] , there is much more versatility with out experimenting with the above concept.. The G1000 will allow you to que a section of a sequence in realtime, that you can go back to, for example late on the floor dancers, when you are at the end of a sequence..