Frederique Constant, keep or trade for used rolex?

[Buckeye4life]

Earlier this year, I picked up a Frederique Constant classic moonphase (not slimline) as a dress watch. I really like the simplicity of the dial, and the moonphase is very cool. It has an in-house movement that is 28k BPM, just like my z blue. It's not COSC, but it runs about -5 seconds/day. I bought it for $1500 on Amazon, and now it's over $3k (closer to retail). I can't find any on ebay. There's a few on chrono24 (is that site valid here?) going for about 1800-3600. It's ref FC715S4H6.

I really like it, but I'm torn about keeping it or not. I love the idea of selling it for more than I paid for it. I feel like it's now or never from that standpoint, because I doubt it will carry the value as long-term as rolex and other more established brands. But I bought it for a reason, I like it, and I think it's an outstanding watch for the price. I never wore the original strap, I replaced it to preserve the original for resale value.

I'm thinking about listing it with a high reserve and if I get 2500 or more, getting a used DJ 1601 and putting a leather strap on it for a dress watch. Or, putting the money towards getting a BLNR. Any thoughts or recommendations?