Pros: Build quality, Warm and well-balanced sound, Ergonomics, Detachable mini-XLR cable.
Cons: No issue I can think of. These headphones beats higher-end ones.
I got these on Amazon for $87 to replace my broken AD700s, and I must say that they are not only cheap (they dropped to $78 lately!) but the sound is great, and warm (but not too much). The new MKII model changed practically nothing (well new looks and an additional cable and pair of earpads) and costs $55+ more, that's why I chose this one.
Overall, sound is pretty well balanced, and bass is just fine (I found that the AD700's were lacking a bit...), also I like very much the fact that they are semi-open: sound is natural, but the headphones don't leak too much sound are aren't too much subject to external sounds.
The soundstage is pretty good too, through it doesn't match the AD700s (yeah AD700s aren't overrated on this one ).
I like very much the ergonomics of the 240, the self-adjusting headband adapts itself to your head's size and doesn't put too much pressure on your head (the AD700s in comparaison were more designed for big heads, it would drop off my head quite easily, was also a bit massive when compared to the K240, which I found to be a bit more comfortable). Another good point is that the construction is very solid (AD700s looks cheap in comparaison since its structure is made of thin plastic and is obviously more likely to be broken), I think they look great too althrough that is subjective.
Oh and I forgot to mention, the cable is DETACHABLE: means that if you accidently break it you can replace it easily; and those mini-XLR cables can be found for quite cheap on eBay and such.
I haven't seen many people talking about the K240 on OCN but it definitely gets my recommendation.
Thanks for reading! I'm open to comments.