Well, I actually find the JH13Pro and ES5 to have distinct sound signatures from each other - the ES5 has a little punchier mid-bass although deep extension, and the JH13Pro has a little stronger deep bass, like there is a subwoofer placed somewhere in the room that's slightly disconnected from the mid-bass. And the ES5 mids are a little more present and vibrant than those of the JH13Pro, giving the ES5 a slightly more forward presentation although the size of the venue still feels big like with the JH13Pro (air, ambience, echoes). The ES5 still feel hyper-detailed like ES3X, like the contrast or saturation turned up a little on a video monitor, while the JH13Pro are slightly smoother and ever-so-slightly laid back in comparison. There is no doubt that with my eyes closed I'd know which one I'm listening to.
The JH13Pro are probably a little "more neutral or less colored" than the ES5, but still fun and exciting to listen to. I've heard the UE18 demo, the UM Miracle demo, and the JH16 demo (universal fit with foam tips that they bring to CanJam at RMAF) and liked those two more than my UE11Pro, but in no way can I compare them due to meet conditions and them being universal fit demos. They all would have made a great sounding universal fit IEM for production. I have not heard the UERM demo or Merlin demo but will do so at RMAF this year if they are there.
I thought that my next custom might be the JH3A/JH16, but I was putting it off until it seems like a finished product to me and then forgot about it as I pursued the Stax SR-009.