Great review! To all who are reading and wondering what this headphone sounds like, @betula's review is truth.
I listen to a lot of fast aggressive metal and hard rock, and by far the CO is the best for these. Second place would be my Ironwood VO (the Ironwood is extremely dense so the sound is faster and more concise than on most VOs). The VO is similar to the CO but more analog in comparison, kind of like a solid state amp versus an equivalent tube amp. I go back and forth, but the CO is better for the metal and the VO is better for the hard rock, especially hard rock with male vocals. I have owned 2 VCs but they are tuned in a way I don't like, with such a high peak in the upper-mids that I have to adjust the volume to that peak, which means the volume is too low for all the other frequencies. I would think, if that isn't an issue for you, the VC would definately be best for metal, if the alternatives are AC and AO. In my opinion, the AO is the worst by far for anything with much heavy distorted electric guitar because it gets quickly crowded and unpleasant in the upper-mid region where heavy distorted electric guitar occupies. Others have made the same observation. Others have said the AC is good for rock/metal. It doesn't have the problem the AO has, but I like detail and clarity and the AC is too slow, bassy and V shaped for that. If that doesn't bother you (I think it doesn't bother most, I just don't like warm), then the AC could be good with metal, assuming it is a hardwood AC. If it is an AC with a softer wood, then it will probably have too much lingering bass for rock or metal, but apparently you can overcome most of this problem with suede pads, so that could be something to consider.I'm also very interested in your opinions on the best ZMFs for metal. Currently own VC, AC, AO. I tend to like more and more both closed cans, Atriums O recently became for me a little too shouty. Now considering selling one the above and getting CC or CO for faster - paced and more complex music. CC is sooo tempting, especially this beautiful limited edition
Great Review! Thank u.
Thanks! I agree with the differences between AC, AO and VC. My AC is olive wood. Seems that I need to give a chance to to Caldera finally!
Thank you! Best lighting comes from the Sun itself, but we could use a bit more sunshine here in England.
I literally ran to the window with all the headphones to have a chance. 
. I'm in the camp of those who were on the fence about the new cup design, but the Shedua sold me.
It's just the weight and a small aesthetic difference. I like magnesium when I can get it, but once the headphones are on you forget about those small details as you are swept away in the music
I think, you can save 34g with the magnesium chassis (or around 30g). I also think, it is worth it.
It spreads out the weight on your head better due to having more surface area. I wear glasses and incidentally I have found I get a better seal too.
BBB strap all the way. The better weight distribution of the BBB strap is far more helpful for me than the magnesium.
That is correct from past experience. It is an added accessory that you have to install yourself. The user would need to remove the default strap and add the BBB strap. That's what I did for my CO that came with the standard strap.
