Just a personal note from a guy who has done this whole dance before (SE535 > CIEMs) you may want to note that CIEMs are quite a different experience in user friendliness, plus fit and waiting time and the larger margin for error. I upgraded to a wizard design Heir 8.A (way back when) and after some unexpected fit issues, sending the CIEMs back and forth, I got to enjoy my CIEMs for a whole of 3 months before I got sick of the inconvenience of the CIEMs form factor. And so, after a while, I'm back to UIEMs, and have since learnt that CIEMs aren't quite for me. Fair warning, this has happened to a few friends of mine too, though I know many who enjoy their CIEMs.
Do note that you can easily get the same sound quality, and build quality out of UIEMs (now that Noble has their K10 universal) and the sheer ease of use has me forever committed to using UIEMs.
That said, the K10s seem like a fantastic choice, but if you do want end game sound with the "safety" of a UIEM, my top picks would be the SE846, Dita Truths, the K10 and AKG K3003.