The CK10 is a great option. It's natural and life-like in sound, extremely detailed and articulate, and is well balanced short of a narrow, moderate peak at 12kHz. In an IEM format, this is one of the better products out there. There really isn't much else out there that is as detailed on the top end as these.
The UM3X can be a contender. It's certainly one of my favorites. It however it's more of a tool than a toy in the sense that it's somewhat artificial in sound. It's very up front in the sound stage putting right on on stage and right in the face of the singer. It's level of detail is extremely high as is its dynamic range. It will show you subtlety and explosiveness, and you will hear things you'll never hear in another earphone. It's well balanced but not the best blended. It does not hide anything and scales directly with the quality of the source device and music quality. It's good about showing you the true nature of the audio track. The downside is that for many it sounds a little boring. It was developed as a monitoring device, and it's well suited for that. Enjoyment comes from listening to great music, but it won't make average music great to listen to. The W3 might be a more favorable route in terms of fun factor.
The SE530 is a very neat earphone. It's dynamic breadth is unmatched. It has pinpoint placement of sounds, although they seem to exist in the wrong spots. Notes are super clean but short on note. Frequency response is mid-centric. I personally found this to be a really interesting earphone and initially very impressive. However, the neat factor wore off the more I listened to it. It simply became more and more flawed. The notes lack articulation and depth of information because they are so short and to the point. You miss texture in the music. The frequency response is likable for certain aspects, but I found the treble to be slightly recessed in presentation. The bass rolls off really early and even a lot of EQing doesn't help. It can barely get to 40Hz even with a massive amount of EQing. The SE530 does certain things better than any other, but I feel there are just better options out there from a holistic standpoint.
I'll point out the RE252 as another contender. It's a midrange and treble geared earphone, excellently balanced and with outstanding extension and detail. It's natural, life-like, and has great dynamic presence. The presentation is slightly direct but also open and spaced. This is one of the best balance earphones I've used although very slightly tilted bright, and it has a very linear frequency response.
If you can step outside of the IEM realm, I would heavily suggest the Yuin OK1 bud. I've owned one for around a year and a half and have owned and sold a lot of high end IEMs in the mean time. I haven't come across anything else that shares the same openness and direct sense of sound, the high detail and articulation, and realism in sound. It however does benefit from a powerful amp and some EQing as it is a high ohm and brightly geared earphone. This is an earphone that I have personally held as the product to beat when I have been trying out other earphones. In terms of total package and providing and accurate, real sound and presentation, this has been my favorite. I have often described listening to a pair of these as like day dreaming music, because that is how it sounds. It's in the head but is so transparent and open that it is as if you're thinking of the music yourself.
Aside from a bud, the CK10 is the only other earphone I've used that offers a lot of realism and very high accuracy and articulate and many traits of this earphone remind me of the OK1. The RE252 is the only other that's like the OK1 in directness and the ability to fool the listener in thinking that a sound heard through the earphone is a sound heard in real life. For me, this is sort of the pinnacle of audio reproduction, having a product good enough in sound to have information perceived as if it happened for real. These have been my 3 favorite earphones out of everything I've used, and they all offer a high level of realism, accuracy, articulation, and dynamic range.
