I am curious about the market for resale on the SMP. I happily bought a SMP GMT 2 years ago at fair market value for a barely used 2535.80. Now, the re-marketers are saying that I will be lucky to back 2/3 of what I paid? Is that right?? Have the markets gone that soft on the 3-5 year Omegas?
Probably, new watches usually get crushed. I don't have a lot of data to back this up, but watches like yours are in the "new, mid to high range" category, and most people that wanted one, already have one. Because of that, the market is more limited when it comes time to sell. Also, there is no scarcity in modern watches, except of very limited editions, meaning that you can the same model 10x over on any given day. Take everything that I say with a grain of salt, as I only buy/sell modern watches for profit to fund my vintage passion. I will say this though, based on what I am seeing on ebay, modern prices are falling across the board.
I don't think the GMT versions are as popular so your pool of buyers is going to be smaller. Also, if the watch is about 5 years old it probably needs a service soon and I would think that has an affect on the price. The best way to know is to check eBay's sold listing and what others are asking on watchrecon.com.