Pros: Musical bass, high separation for closed can, sparkly treble without fatigue, looks, removable cable, imaging
Cons: High MSRP, bass slant may be too much for some, weight, not suited for small heads.
I went into a local business that had these on display, and after trying them I decided I enjoyed them more than enough to get them . . . assuming I could get them substantially under MSRP which I did. Let's get started on the good, the bad, and ugly.
Very easy to drive, you won't need an absurdly powerful amp to drive these and get the best they offer. The bass is strong and punchy while avoiding one note syndrome, listening to Red Hot Chili Peppers with these is an absolute joy. I've found these place emphasis on the bass, but tend to avoid messing up the mid-bass drastically leaving vocals mostly unaffected for music I've played with it. Of course electronic and metal has also benefited from this. One would expect the treble to suffer, but it's one of the first cans that I've found with an enjoyable sparkle that is non-fatiguing. The treble strikes me as more present than my K702s.
Build quality seems reasonable. The cable is removable which is always a good sign.
The style is very modern. It will obviously resemble Beats some, but the leather pad stitching and white accents adds very distinctive flair.
Very comfortable, especially for those with large heads. I have a XXL head according to my hat size, and I'm only a couple notches or so out on each side.
On sound I discussed the bass and treble some. With how the headphones are tuned it seems to thrown the balance off some. While separation is good and everything still sounds coherent, the mid-range tends to sound smooth without any emphasis in its own right. Depending on what you tend to focus on when you listen to music, the bass and treble may come off as merely distracting from the rest. I feel it captures a more "live" sound for what it's worth - but it's worth watching for.
The weight of these cans can take getting used to. I have a pair of Monitor 10's at this time, and the weight is around that territory. For a plastic can this comes off as unexpected, but it seems that the weight was increased to help increase reliability all around.
Not particularly portable, the size of the cans and the above pretty much shows why.
Those with small heads likely need not apply. This can seems to be distinctively made for those with medium to XXL heads.
MSRP too high for regular purchase. The D5K justified its price a bit more due to its reference qualities, as a fun can this justifies about ~60% its asking price. I'd only purchase this after having experience with real reference cans and knowing exactly what you're looking for and enjoy in a "fun" can.