Omega Railmaster Query

Firstly ask yourself can the cheap one be put back to mint at just the outlay of a service, or are additional parts such as a crystal, dial, case, bracelet etc necessary*. Those are not included in a std service and none are cheap any more.

Next do the maths. Is the cost of the cheap one plus the service (plus any additional parts) lower than the cost of a mint recently serviced one (if you can find one). You should then have your answer. I suspect the known commodity of the serviced one will prove the more dependable and cheaper option but that's for you to ascertain.

*note the factory will only remove material by refinishing, they wont add it in by laser welding which a specialist might, as such deep dings can remain after a service. The factory only offer to refinish or replace.

ps I once bought a very cheap 39mm RM from ebay at a give away BIN price. Then I found it had an undisclosed crystal scratch and the service cost was painful so I am not making this up!

I'd probably try to find a really good deal on a used one off eBay then service it, as pretty much all of them are going to be due for service as this stage. Even when eBay sellers say they've had it serviced it's usually a DIY or dunk and swish type job rather than a proper job by an Omega certified watchmaker.

I wrote about these here btw if you'd like some more info: https://stories.omegaforums.net/what-happened-to-the-2000s-omega-railmaster/

Well there is a saying, trust but check. What I mean by that is, if a seller claims a watch has been serviced, ask to see written proof. No proof then evaluate it as if a service is needed.