Like Simon said, some RDs were recorded (I think) with MIDI kits, so the notation for these include all the MIDI data.

That's a really cool feature. Not on all RDs have this, but the ones that do have it may surprise you.
Of course you still need a decent drum synth to play and 'hear' it.

For some of these tracks, if you are a savvy user, you can also go into the raw RD track, and at the end of the file you will often find individual drum hits, which can be very helpful in multiple ways (especially when combined with the MIDI data);
you can build a new drum synth patch with these 'samples' and have the same sound drum but triggered by MIDI,
you can use a different drum synth with just the MIDI
or you can copy various drum hits from that raw RD track as audio snippets, and then paste them as needed.

All different ways to accomplish what you need.

I do not work here, but the benefits are still awesome
Make your sound your own!