Really love hearing everyone's feelings about Monachaa, an iem I demoed on the Watercooler tour, and rather promptly thereafter, bought my own. So yeah, I obviously like it very much.
Couple of things I've noticed about it, which have been mentioned by others as well...
It takes a solid 200 hours of burn in, this is pretty imperative. It takes a lot of power, good power, to drive. This takes my DAPs to high gain, so I doubt cheap dongles will make a happy listener. It's highly tip dependent and has a particularly short nozzle; my preference here has become Coreir brass tips which work well on short nozzles and usually do nice things to the SQ and stage (I've also used the Penon black liqueur tips to great effect). Finally, nice as the included PWA cable is, Monachaa needs better. I've had great experiences with PWA FT, EA Code 23 and 24 (would like to try 24c on it, the colors should be great), and Penon Renata.
When dialed in, you understand why Oriolus has such a good reputation for tuning. This one is outstanding! Deep, sub bass, with thick mids, vocals a little forward evoking a V to U shape, treble to rival Anni 23, and a soundstage to die for.
IMHO, a contender for best at $2k or under (and certainly better than many $3k+ plus sets I've heard!). If course, YMMV, etc., just my opinion!