it probably goes without saying, but nobody's under any obligation to enter both, and indeed i assume most folks will "choose one". the only thing you can't do is submit the same entry to both. they'd need to be separate entities
if this goes over well, i'll amend the bitpack .txt to be more specific about this "double format" thing. remix is totally normal, SNES restricts you to a sample pack w/ no built-in noise generator (that you probably would not have used anyway)