Bombs away. Obviously Hilton was more proven as his career actually played out. I think these two had similar strengths and weaknesses. I'll go with Hilton just because we know what he had. Ayala never faced top level completion so we really don't know.
Prime Hilton was a 80 's version of Lemieux . Hilton was very impressive in winning title from Drayton but after that fight ill discipline meant he like Ayala he never fulfilled his enormous potential. Hilton at his best mauls the bully Ayala and a exhausted Ayala does not come out of his corner after 10 rounds.