I think at the end of the day, there are only standings on a personal level and on the market value level. Anyone can give any ranking on a personal level. But for a market level, the standing for the 5 would be Rolex, Panerai, IWC or Omega, Breitling. Panerai is not so consistent on the used market as some models ( the brevettatos and the marina militare) fetch a very hefty price tag whilst others (historic and contemporary range) fetch a good price depending on the season and demand. The chrono, regattas and the smaller models dont do very well in the market. This is my experience as I was selling my collection to fund for grails. Just my few cents.