We got the ticket for The Breakers and one other house. We chose Marble House, based on the reviews here. However, as lovely as Marble House is, we felt it was 'more of the same'. In retrospect, we would have preferred to have chosen a 2nd house that had a slightly different feel to it than The Breakers. (ho hum, more over the top opulence!) That said, as mentioned, the audio tours at both places were very well done. The ticket taker at The Breakers suggested The Elms, so that might be an alternative others might consider.
If you own or manage Newport Mansions, register now for free tools to enhance your listing, attract new reviews, and respond to reviewers.