I have not a single DD among my IEMs, but I am very curious about how they hold up, as they get a lot of praise.
But which one to get?
Soundtracks is a major part of my music, so something that works with that kind of music is my aim. And to be used OTG with my Cayin N6ii DAP.
A single DD with EST could also be interesting (Thx for the insight @Rikudou_Goku)
Fiio fd5, tanchjim oxygen and the Sony ex1000 (with EQ) are my recs.
I really like the JVC FD01/X1 for the price. While I enjoy the Campfire Atlas for a fun change of pace, I couldn’t recommend as a daily driver
Same with the Vega…I get down with that set when the mood fits 
From my listening and collection the fdx1 at 200ish is great for audiophile anylitical listening, aka the stereotype lol. But for me its lean so my main pick has been the little brother ex800st. It is warmer while still being clean and is still neutral overall as well due to the studio use it was intended for. With either the ex800st or the ex1k keep in mind that treble may be too peaky if it doesnt have the foam filters in good condition. Or may still require tweaking even if they are present.
i understand if you’re aiming for expensive. But if you don’t even own one set of DDs, why not take the pleasure to start low and buy yourself a bunch of wonders like Tin T2, Blon BL-03 and (especially) the Kbear Believe? You will understand what separates them from more “complicated” IEMs and you really might enjoy them much more then you’d expect for the price. DD is a treasure trove imo.