The Rolands can't do both at the same time, nor replace the SMFs drumtrack with an arranger one (great feature), but primarily, I was interested in going seamlessly from SMF to arranger and back to give me a quasi-chord sequencer ability, since Roland dropped my favorite arranger feature.

Are any of you using it in this way? The ability of the Roland to combine both modes with the SMF Marker function makes back and forth very easy.