Got mine in. I'm a harsh reviewer. Be prepared.
Five minute inspection:
-Those are some small headphones...Thought they were bigger. The earcups feel smaller than the Sony MDR-V55.
-ah cheap plastic headphones, we meet again. Oh but the earcups are metal at least.
-the cable is too thin so it hovers instead of laying flat on the surface and out of the way. This leads to snagging, which has happened already. Can be fixed by just making the cable thicker with sleeving.
-Heard a CRACK while adjusting the headband. Did I already break them? Upon inspection, the headband is made of three pieces and is hard plastic. There is no cushion on the outside of the headband.
-Sharp edges everywhere. I felt this thing poking the sides of my head above my ears. I took it off instantly to see what it was. It was the hinge. The hinge was touching the sides of my head!
-I always grab the adjustment band area to take off headphones and there's really sharp angles right there!
-Adjustment notches are too loose. If you take off the headphones, they slide in and you have to readjust them.
Without even putting music on, I hate them.
Only used the K618DJ a few hours, so maybe they haven't burned in yet, but here goes. I've had the PRO700MK2 for about a year now and have used them very often. Over time, I started to not like them because I could point out the flaws as I gained headphone experience. I honestly hate the sound quality from them now, but the build quality is still amazing.
First before I listen to headphones, I put music on and put them over my thigh to test for isolation, because that is about the thickness of my head. These pass my sound leakage test at the usual volume level, which is about 80-85% of the Sansa Clip Zip.
VS PRO700MK2
-Bass: They both are bassy headphones, but the K618DJ has more bass quantity, but maybe a little boomy, but not muddy. The PRO700MK2 is more bright, so there appears to be less bass to me, or maybe it's just tighter bass. The bass on the PRO700MK2 seems to have more detail though. There is a lot of bass on the K618DJ, but it does not vibrate the housing like the PRO700MK2, probably because of the kind of thick plastic that they used. To me, neither of these headphones punch like the TMA-1 or TMA-1 Studio, so don't expect subwoofers on a headband, like people say. Both are good enough for bassheads, but since the K618DJ has more bass quantity, maybe it wins.
-Vocals: I never liked the vocals on the PRO700MK2. I can't explain it, it's just not clear and it starts to annoy me over time. On the K618DJ, the vocals are really clear compared to the PRO700MK2. Very much enjoyable. K618DJ wins easily.
-Live drums - again, the PRO700Mk2 has more drum detail, but the K618DJ still does sound good. On some rock songs, because of the bass, the kick drum feels like it's really close to your head with the K618DJ.
-Electric Guitars - Yet again the PRO700MK2 does it better because it is more detailed. The guitars on the K618DJ are less forward, but still very good since you can distinguish separate guitars.
-Detail - they both can pick up the subtle details well. You can tell layered vocals, effects, and guitars with both. Not like Shure SRH940 detail, but more revealing than lower end headphones, especially for bassy headphones....hmm I'm not sure which wins, but I'm really enjoying the K618DJ. These are two bassy headphones that have good detail.
-Treble - as I said earlier, I think the PRO700MK2 has too much of it and it starts to annoy me. The K618DJ wins in not being an ******* with the treble.
In short I think the K618DJ sounds better than the PRO700MK2. Yeah, I said it. The headband needs to be at least a centimeter wider so that the hinges aren't touching my head for it to be an amazing headphone for $99. Possibly I just really hate the vocals on the PRO700MK2 enough for me to like anything else, even if it is less detailed.