OK so I have an omega speedmaster.
Thinking of adding in either:
- Rolex Submariner (No-Date)
Pros: Classic, works with any outfit, won't look dated in the next 50 years
Cons: Already have a black speedmaster and this may be too similar in a small collection, slightly ubiquitous.
- Rolex GMT-Master II (Blue/black)
Pros: Unique world first two tone ceramic, GMT/date function, in the context of starting my collection it adds more interest with the color scheme, less common
Cons: Will the color mean it is less classic, or will I get bored of it after a few years?
A no date Sub C is about 2k less, so if you want to go on the cheap.....
All things being equal, I'd go for the BLNR seeing as you have the Speedy. If you do get tired of it you can readily sell it.
Either one will be an excellent addition to your collection, IMO.