I would have to say a Patek, I have ordered one and I already own a rolex, tag and cartier. The Patek is a really well made watch.
It is also one of the only companies that interviews it customers before you can purchase a watch!Lol!! Not all of them but certain ones that go up in value very quickly. A lady on this site called Bee Bee has one or a few and if she sees this thread, I am sure she will give you some useful advice!
I have only one since I sold my 4936G and it's a lousy quartz
; the 4910/10A Twenty~4. You have to talk to my husband about Pateks because he is the one wearing the 5296G and 5070G (actually we just got the latter one last weekend in Monaco so now I am broke again, LOL).
But to be honest nowadays I am not so keen on Patek styling (I am currently obsessing over my Breguet La Tradition) except the 5970G with a 2.5 year list and the 3939HP which I will have to wait 4 years with the interview!
Coming back to the original question on watch brands, it is really weird but if a lay person can quote a watch brand it probably means it's not prestigious - you can say this is bordering on snobbish by the watchnuts if you like. Rolex is definitely not prestigious because it's produced in millions a year. Chanel, TAGs, etc. are definitely low down.
If you want prestigious, you want Philippe Dufour Simplicity (but then 99.9999% of the world's population probably haven't heard of Philippe Dufour
). The finish on that Simplicity is better than any Patek, let alone Rolex. If you have one you have made it, LOL and it will be very prestigious because there are only about 10-20 made a year and the list is full to 2009 and after that no more!
Perhaps this is a good table to see where things are (to show especially that the Chanels, the TAGs, the Rolexes are not the ultimate). I don't know the budget of the lady who started the thread so she can work it out herself!