I'm not familiar w/ the old Boss BR but I think the 864 drum and COSM effects are terrible. You can load in wav/aiff files and create custom kits but I never bothered because programming odd time is a nightmare and you're stuck w/ mono. Here's my "I-can't-afford-to use-my-hard-drive" bandaid for the issue of drums w/ the BR-864 if you have a PC:
I have Cool Edit 2.0 on my PC, I've searched the web for all the free loop wav.s I can find that I like; there are tons of sites. Create a stereo loop in Cool Edit (you can chop 4/4 and long passages into interesting odd time loops..... sometimes), mix it down or save it as a wav. Convert to MP3, burn to CD and record the CD thru 2 tracks on the BR. I'm sure you could find freeware that does the same thing as Cool Edit.
It's convoluted and inefficient but it works for me until I get Reason.
Jeff
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