Re: Drum Machines that play MIDI files
The SR-16 presets, as I understand it, were played directly into the software by studio players, so the "human" aspect is retained through Quantization.
As for being able to create a MIDI drum sequence on the PC and load it into an external drum machine, nothing does that, to my knowledge. The only way to get it done is to use a MIDI interface for your PC running out to your external drum machine, and the audio outs of the drum machine running into the PC (Line In, USB, etc).
Your program (sequencer) also has to be set up to use the correct MIDI Out port (default is internal synth).
However, if you're going that route, and you're not going to program the drums in the unit yourself, you may as well go for FXPansion BFD 2. It has way better samples than any drum machine, and it can load in MIDI drum files easily.