What time is it? Watches and horology

Keep.

Is there even a glass on there? I'd keep it.

Here's todays cheapo. Needs new bezel.

Does it make economic sense to sell?

If it's just about reducing space/collection I'd sell it.

Keep unless there's real-world reasons to get rid. It's a beaut. A strap change or leaving it off the wrist for a bit may help make up the mind?

Le sex!

I've always had a soft spot for the railmaster.

It is really your choice, but since you ask - I thought you were building quite a nice Omega collection. Why break that up to get a Rolex GMT? I thought a more interesting next step was the Ploprof.

Do you want to be someone with a rad Omega collection, or someone with a GMT, a fantastic watch, but so well known and desired that it is almost generic?

sell. the 1940 you got recently is much better looking with more strap options. plus you have the tintin for a sportier look.
usually when somebody asks keep or sell its because they want to sell. its just a watch. i say sell..