Personally i think it is all about rebranding. Remember Tag Heuer, it was Heuer who was the watch maker then die off 1960s like most of the watches, it is Tag company who bought and merged into Tag Heuer and came out the first version of Tag Heuer Formula-1 late 1980s capitalised on Ayrton Senna popularity in the Formula One racing with Honda, since then the watch has evolved into one of the top brand after all the money spent in the rebranding exercise, only after that Tag developed their in house movement, other ETA has been supplying them all the movement like how ETA works with Cartier, Omega and many more brands.m
Rolex has got their own movement since early time, but not for Daytona the most highly sought model is 16520 with Zenith 400 movement, and strangely Rolex finally came with in house movementof 4130 in 2000 onward, the collector is not interested on Rolex In House movement but pay premium for the older model of Zenith movement.
So, it is really depend how the branding, marketing, rarity that will determine the popularity. Unfortunately ETA is a common name and mass production manufacturer, good reliable products but also widelyused by many players, therefore it is naturally becoming less special, i think Panerai in house movement is getting the attention now. But the question asked, which model of Panerai commanding most value now? Definitely not the latest newer model with in house movement, it is those produced before 1990s that highly sought by collector.