Disclaimer: I'm not much of an experienced reviewer so I apologize in advance for any misuse of terms. I also wanted to say that I have not done any other mods than expanding the headband.
 
A couple months ago I bought $60 headphones. I didn't really know about the brand very well -- I just recognized the name AKG from the Quincy Jones line and saw that they were 50% off. What were these mystery headphones we speak of? Why, none other than the k518LE, which is essentially the k81DJ.
 
Now that I've read more Head-Fi, I'm familiar with the AKG brand name and as more and more time goes on, I'm glad that I picked these. I do spend a good chunk of time with other headphones but I'm glad to always have these to fall back on. They're a bit small (for me), the leather pads get really uncomfortable, but I can sacrifice that for the great sound these provide.
 
Accessories:
These came with a small carrying pouch that I lost and a 1/4" adapter I never use (though I plan on buying a better amp sometime soon). Pretty much standard fare for a pair of circumaurals so there's not much to say here.
 
Build:
The build is simply put, solid. It's compact and really portable and yet it still feels like it can take a little bit of damage (a little). I'm really being nitpicky here, but the wire gets tangled too easily and I don't have the time nor experience to recable it. On a side note, the paint's chiping D:
 
Comfort/Isolation:
These isolate pretty well - so well in fact that I can serperate myself from what's going on around me (on second thought that might not be the best thing). In terms of comfort, it's a little bit more unpleasant. I have a larger head and it is a bit of a tight fit. I have left these overnight hanging over a textbook and that has helped with this tightness problem a lot though it can get a bit uncomfortable. On another note (as stated earlier), the leather pads can really get warm and a bit uncomfortable - I intend on ordering HD25 pads in the near future. (Sorry for focusing so much on the negatives - I can't emphasize enough that these are good but I find it kinda hard to describe without repeating myself).
 
Sound:
If you get the other three behind you, this is where these headphones really start to pay off. The sound is a bit on the bassy side but then again, they're DJ headphones not studio monitors, so what do you expect? There's a reasonable amount of balance though EQ can help in this area. The k518's respond well to EQ but regardless, they're good for listening straight up - they deliver the fun signature without going overboard and taking you into Beats land.
 
Value:
At the current price, I can't think of a better on ear headphone (assuming CAL! is not on sale at time of reading). It offers punchy bass with reasonably good overall sound with a few caveats. I highly recommend them.

 

Here's a bargain bin favorite that has withstood the tests of time. It may remind you of value headphone (the AKG k240) but before you label it some cheap knockoff, take some time to give it a listen. No, the Superlux does not outdo its AKG brethren, but instead offers a bassier, "fun" sound that is perfect for the $37 asking price. (Also, I cannot speak about packaging I tried the headphones off a friend)
 
Appearance/Build:
In terms of originality, this is a complete failure. But that aside, these headphones will look polarizing to any non-dedicated audiophile. That being said, let's face it: the K240 is probably one of the better looking studio headphones out there, and imitation is the sincerest form of flaterry. As for the build itself, I'm kinda stuck somewhere in the middle; the headphones are mostly plastic and seem to be on the cheap side, but they really feel like they could take a hit, and they lasted a day in my school backpack.
 
Isolation:
These are semi-open headphones which is basically a fancy way for saying the isolation sucks. Open headphones have holes behind the drivers which are intended to create a more free sound -- this benefits natural balance and soundstage, but it sacrifices the isolation. That being said, the isolation is better then my 535's which I compared them to. And to be honest, these have really good isolation for an open headphone, but at the end of the day they're still open.
 
Sound:
This is where in my mind, the Superlux start to redeem themselves. Though marketed as "Studio Monitors" the Superlux are slightly colored. That being said they hold up were a majority of open headphones struggle: the bass has enough presence to make itself felt. On the flipside, unlike some closed headphones (cough, Skullcandy, cough) the Suerplux keep the bass on control, though they do lack some of the extension of closed headphones (the open design prevents this).
 
In regards to the rest of the spectrum, sorry for not paying more attention to those details. The mids are full in quality and rich; the highs are vibrant and I experienced no fatigue. I just really wanted to point out the bass here because it's amazing... at least for an open headphone.
 
Value:
I don't think open headphones get any better than this in the price range. Maybe Superlux's own HD668B can outdo the 681's, but these are still impressive... period. For $40, they're an absolute steal.

I bought these as a replacement for my lost CX 300's, which IMO, were pretty good for the price I paid. These $10 earbuds quickly surpassed my memories of my CX 300's--they sound amazing for $10, and amazing, period. When I listen to these, they sound like they're worth easily 3 or 4 times the price.
 
The bass is very prevalent in these. For a lot of my music, that's a good thing but the few times I've ventured out of electric and rock genres the sound comes out kinda muddy. They definitely have a really mainstream signature - the bass is boomy, the mids are clear, but the highs are recessed. On a side note, getting a good seal is crucial with these. I replaced the stock tips with Comply's and wow, it really did sound different.
 
The cables are slightly microphonic, but the cable itself is really strong and doesn't tangle that bad. Overall though, it's a really good deal at $10.