I'm not sure how you received 808 samples from the original ROMs - all the 808 sounds were synthesized. On the 909, the hats and cymbals were samples.
Almost everything I do is based around a minimal set up of Audiorealism's ABL3 and ADM, and some samples. Although I will often end up with 2 or 3 instances of ABL3 playing different 303 lines.