I voted for 'Appetite' although there's merits for both albums. 'Nevermind' was a refreshing break from the "Hair Band/Hair Metal" music of the late '80s- of which G 'n' R associated with. I was in High School when 'Nevermind' came out and it ushered in Grunge to the mainstream. I think this album is more impactful to kids who were looking for something new. (I never owned the album)
'Appetite' is a top-to-bottom tour de force, IMO. I originally had the cassette and songs like 'My Michelle', 'Mr. Brownstone' and 'Paradise City' just kicked my @$$ with the sounds from Slash, Steven Adler, Axl and the rest put out. As 5th-grader it was the best; G 'n' R may have been lumped into the Hair category but their music set them apart from the others- in a way ushering in Nirvana, STP, Pearl Jam, etc. a few years later.
My ¢¢