dps100502598

I saw many people below saying they go with a bigger size in the miura than in the mythos. I think that they are not sizing this shoe properly.
The mythos is designed for your toes to be flat, much like a normal shoe, whereas the miura is designed for your toes to be curled / scrunched (which is what makes it stronger at edging). Accordingly, you're going to want to go much smaller in the miura than the size you would wear in the mythos. Otherwise there's really no point in getting the miura -- your feet won't fill up the shoe properly, it won't function as designed.
For my feet, and for my climbing purposes (sport, gym), a 39 in the mythos and a 37.5 in the miura seems to be appropriate. I found that as I tried progressively smaller sizes, it didn't really get any less comfortable, though each time I could feel my foot filling the shoe more fully. For me, in the store, the 37.5 was very difficult to put on, and was a bit painful when I walked in it. My foot also cramped up a bit. But, after a few weeks of climbing 3 days a week, it has stretched a bit and I think it is absolutely the right size. Now it is comfortable enough for a few pitches. I believe in the future it will become still more comfortable. I On the basis of that, if you're looking to use this for sport or gym, I recommend shooting for a sizing experience similar to the one I describe (if, that is, you're sizing the miura). Of course, your mileage may vary.
But remember, if you don't want to scrunch your toes up, you should probably just get a different shoe, or stick with the mythos.
Hope that may help you shoe buyers/sizers in some way.

This thing is a great design, no doubt. You know what it does. I just want to speak to the difference between this and the ATC XP when belaying a leader from below. The Guide's slots are a little narrower than the XP, so if you're using a fuzzy rope or a thicker rope then the XP will be easier to work with. The XP also has more teeth FYI. And the metal piece between each side of the device protrudes down further with the Guide, but I haven't figured out what the effects of that is. So if you're primarily gym climbing you might be better off with the ATC XP or ATC Sport. Then you can get a Guide if / when you start doing multi-pitch.