Well, just opened the box and stuck in the Mylarone X3s, and doing an A/B test with the M5s, and I have to say, I think I prefer the X3s. Keep moving back and forth, and to my ears, the X3s are the perfect canalphone sound for the price. Using PA2v2 amp, and also unamped, and the X3s just sound better. I have no technical reason to say so, just the sound is more detailed, inviting, clean, etc. I certainly have to give it more time, but if this holds, I will be selling off the M5s. One thing I don't like about the M5s is their form factor. Hate wearing IEMs over the ear, and they have a funny shape for hanging down (doesn't anyone by Ety see the value in the clip?). Anyway, a few days and I will know. But out of the box (no burn-in even), the X3s just sound spectacular to me. Mindset? Not sure. But going back and forth, and forth and back, and all things equal (EQ, volume, etc.), the X3s are in the lead.
Oh, I changed to the small tips I got with a set of Creative EP-630s. The smaller tips give me a good isolation, much deeper. Very comfortable. Didn't like the mediums as much, and large is too large.
Might be down to the ER4Ps, PK1s and X3s soon.