There's one thing to keep in mind - in case of Omega, you might also want to look up indie watchmakers certified by Omega, and thus with access to Omega parts. The ETAs that Omega used, and by that I mean the 2892 with and without modules, were altered by them. Not really any performance boost there - instead, what suffered was the interchangeability of parts. So, in case something needs to be replaced, for the most part you can't use stock ETA or DD replacements.
Module components can also be hard to come by, as the Omega SCs usually just replace the entire module when it's a part of the chrono assembly that goes wrong.
As for Rolex, what I've noticed is the abundance of mooks bragging about how their watch kept going for 15 years without a service... Aegler automatic movements can tolerate a lot of mistreatment, but when they stop working, this usually means that the balance staff pivots have disintegrated. Which usually means the need for a new balance staff. If you go for a Rolex, make sure it's in working order, and if the seller doesn't know when has it been serviced last, have it treated to a basic service before wearing it. You never know if the previous owner(s) of the watch ever bothered to read the manual, and the section about care and maintenance in particular.
I always hope for the best. Experience, unfortunately, has taught me to expect the worst.
Elim Garak, Star Trek: Deep Space Nine
No good deed ever goes unpunished.
Rule of Acquisition no.285